Copper foil provided with dielectric layer for forming capacitor layer, copper clad laminate for formation of capacitor layer using such such copper foil with dielectric layer, and method for producing such copper foil with dielectric layer for formation of capacitor layer

ABSTRACT

To provide a dielectric-layer-provided copper foil or the like for extremely improving the product yield while making the most use of the increase effect of an electric capacity of a thin dielectric layer using the sputtering vapor deposition method.  
     In the case of dielectric-layer-provided copper foils respectively having a dielectric layer on one side of a copper foil, the dielectric layer  6  is an inorganic-oxide sputter film having a thickness of 1.0 μm or less and formed on the one side of the copper foil in accordance with the sputtering vapor deposition method and the dielectric-layer-provided copper foils for respectively forming a capacitor layer, characterized in that a pit-like defective portion generated on the inorganic-oxide sputter film is sealed by polyimide resin are used.

TECHNICAL FIELD

The present invention relates to a copper foil provided with adielectric layer for forming a capacitor layer, a copper clad laminatefor forming the capacitor layer using the copper foil provided with thedielectric layer, and a method for manufacturing the copper foilprovided with the dielectric layer for forming the capacitor layer.

BACKGROUND ART

It has been generalized in recent years to form a capacitor structure bya method same as the method for forming a circuit shape on an innerlayer portion of a printed wiring board, particularly of a multilayerprinted wiring board and use the capacitor structure as an embeddedcapacitor. By forming the capacitor structure on the inner layer portionof the multilayer printed wiring board, it has been possible to omit acapacitor set to the outer layer face, decrease an outer layer circuitin size and increase the outer layer circuit in density, decrease thenumber of surface-mounted components, and simplify manufacturing of aprinted wiring board provided with a fine pitch circuit.

The capacitor structure using a copper clad laminate is formed by usinga both-side copper clad laminate constituted by so-called both-sidecopper foil layers and a dielectric layer located between the bothcopper foil layers, thereby etching the both-side copper foil layersinto a desired-shaped capacitor electrodes, and forming a capacitorstructure obtained by holding the dielectric layer between the both-sidecapacitor electrodes at a purposed position.

Moreover, it is obtained as a basic quality for a capacitor to have themaximum electric capacity. The capacity (C) of the capacitor iscalculated from the expression of C=εε₀ (A/d) (ε₀ is dielectricconstant). Therefore, to increase a capacitor capacity, I. the surfacearea (A) of a capacitor electrode is increased, II. the thickness (d) ofa dielectric layer is decreased, and III. the relative dielectricconstant of the dielectric layer (E) is increased. It is only necessaryto use any one of these methods. Therefore, to decrease the thickness(d) of the dielectric layer in the above Item II., a method for forminga dielectric layer as a thin film by using the so-called dry method suchas a sputtering vacuum deposition method or a vapor-phase chemicalreaction method is adopted.

The technical background described above is disclosed in Japanese PatentLaid-Open Nos. 10-27729 and 2000-178793.

However, the sputtering vacuum deposition method is superior in a pointof forming a very thin film but as the thickness decreases, the qualityof a formed film tends to deteriorate. That is, in the case of a thinfilm of 1.0 μm or less formed by the sputtering vapor deposition method,deposition of an object to be landed of a component to be landed at thetime of vapor deposition becomes ununiform and many pit-like detects areobserved.

In this case, troubles caused by the present of pits are specificallydescribed below. For example, a case is assumed in which a thin film oftantalum oxide is formed as a dielectric layer by the sputtering vapordeposition method on one side of a copper foil used as a lower electrodeand an upper electrode is directly formed on the dielectric layer and touse the upper electrode as a copper clad laminate for forming thecapacitor layer of a printed wiring board. In this case, when a pit-likedefect is present on the dielectric layer, a short circuit occursbetween the lower electrode and the upper electrode at the presentposition of the pit, the function of a capacitor does not work, and theshort circuit becomes a factor for deteriorating the product yield.

Therefore, a component material used for a copper clad laminate forforming a capacitor layer capable of greatly improving the product yieldwhile making the most use of the advantage of the increase effect of theelectric capacity of a thin dielectric layer formed by the sputteringvapor deposition method and a method for manufacturing the copper cladlaminate are requested in a market.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 to 6 show schematic sectional views of a copper foil providedwith a dielectric layer of the present invention. Among FIGS. 1 to 6,FIGS. 2 and 6 illustratively show a case of using a copper foil providedwith a carrier foil instead of a copper foil.

FIGS. 7 to 22 are schematic sectional views showing the variation ofcopper clad laminates for forming capacity layers obtained by using thecopper foils provided with dielectric layers shown in FIGS. 1 to 6.

DISCLOSURE OF THE INVENTION

Therefore, as a result of earnestly studying, the present inventors etal. has conceived a dielectric-layer-provided copper foil for forming acapacitor layer shown below, a copper clad laminate for forming acapacitor layer using the dielectric-layer-provided copper foil, and amethod for manufacturing the dielectric-layer-provided copper foil forforming a capacitor layer.

A. Copper Foil Provided with Dielectric Layer

<Basic Configuration of Copper Foil Provided with Dielectric Layer>

The basic feature of a copper foil provided with a dielectric layer ofthe present invention for forming a capacitor layer is “in the copperfoil provided with the dielectric layer on one side of the copper foil,the dielectric layer is an inorganic-oxide sputter film having athickness of 1.0 μm or less formed by the sputtering vapor depositionmethod on one side of the copper foil and is obtained by sealing a pitdetective portion formed on the inorganic-oxide sputter film withpolyimide resin.”

FIGS. 1(a), (b-1), and (b-2) show schematic sectional views ofdielectric-layer-provided copper foils 1A and 1A′ for respectivelyforming the capacitor layer. That is, as shown in FIG. 1(a), whenforming an inorganic-oxide sputter film 3 at one side of a copper foil2, a pit-like detective portion 4 is produced therein. Therefore, bysealing the pit-like defective portion 4 with polyimide resin 5, adielectric layer 6 formed by an inorganic-oxide sputter film 3 andpolyimide resin 5 is constituted and becomes a dielectric-layer-providedcopper foil 1 of either conformations of FIG. 1(b-1) or FIG. 1(b-2).FIG. 1(b-1) is an image obtained by embedding and sealing only thepit-like defective portion 4 of the inorganic-oxide sputter film 3 withthe polyimide resin 5 and FIG. 1(b-2) is an image in which the polyimideresin 5 embeds and seals the pit-like defective portion 4 of theinorganic-oxide sputter film 3 and a thin polyimide resin layer coversthe surface of the inorganic-oxide sputter film 3. However, thethickness of each layer shown in drawings in this description is notobtained by directly reflecting states of real embodied products but itis emphatically shown so that description is easily understood.Moreover, the same symbol is used to point out the same portion as muchas possible.

<Copper Foil Constituting Dielectric-Layer-Provided Copper Foil>

General copper foil: A copper foil constituting adielectric-layer-provided copper foil for forming a capacitor layer ofthe present invention is described. The concept usable as a copper foilis used a concept including a copper foil obtained through theelectrolytic method and a copper foil obtained through the rollingmethod. Moreover, concerning a copper foil, even if using the so-calleduntreated copper foil to which roughing or rust proofing is not appliedat all as a copper foil or using the so-called surface-treated copperfoil to which the surface treatment obtained by properly combiningroughing for attaching minute copper particles to the copper foil toobtain the anchor effect for improving the adhesiveness with hedielectric layer 6 and/or rust proofing for preventing oxidationcorrosion is applied, there is no problem. Drawings in this descriptionrespectively show a case of using an untreated copper not undergoing asurface treatment is used.

Carrier-foil-provided electrodeposited copper foil: Moreover, todecrease the copper foil 2 in thickness, it is also possible to use thecarrier-foil-provided copper foil 7 shown in FIG. 2(a). Thecarrier-foil-provided copper foil 7 is a foil obtained by combining acarrier foil 8 and a copper foil 2 together through a junction interfacelayer 9. When using the carrier-foil-provided copper foil 7, it is onlynecessary to form the dielectric layers 6 shown in FIGS. 2(b-1) and2(b-2) on the surface of the copper foil 2 of the carrier-foil-providedcopper foil 7 and form them into dielectric-layer-provided copper foils1B and 1B′ followed by the carrier foil 8. Moreover, it is onlynecessary to form an upper electrode on the surface of the dielectriclayer 6 by a method to be mentioned later and then, remove a carrierfoil.

Copper foil provided with binder metal layer: The binder metal layer isused to improve the adhesiveness between a dielectric layer and anelectrode forming layer. Therefore, as shown in FIG. 3, the binder metallayer 12 is set so as to contact with the dielectric layer 6. Moreover,a material having the best adhesiveness with a material used toconstitute the dielectric layer is properly selectively used. However,when the binder metal layer described above becomes too thick, it isdifficult to remove it through etching and the binder metal layerbecomes etching remainder. Therefore, it is preferable to minimize thethickness of the binder metal layer.

It is enough that the binder metal layer 12 is a very thin metal layerhaving a thickness such being 30 nm to 0.5 μm and it is considered thatforming the layer by a dry method such as the sputtering vapordeposition method is the most suitable manufacturing method. Moreover, abinder metal layer capable of improving the adhesiveness between anupper electrode forming layer and a metal-oxide sputtering layer orpolyimide layer uses any one of such materials as cobalt, chromium,nickel, nickel-chromium alloy, zirconium, palladium, molybdenum,tungsten, titanium, aluminum, and platinum. Furthermore, it is possibleto use the binder metal layer 12 by considering the consistency with thematerial of a layer with which the layer 12 contacts and thereby formingany one of the above materials into a plurality of layers.

Copper foil provided with high-melting-point metal layer: Moreover, itis very advantageous to form a high-melting-point metal layer 20 on thecontact face with the dielectric layer 6 of the copper foil 2. FIGS.4(a), 4(b-1), and 4(b-2) show schematic sectional views of adielectric-layer-provided copper foil when the high-melting-point metallayer 20 is used. The high-melting-point metal layer prevents thecontact with polyimide resin used for sealing to be described below,functions as a barrier for preventing copper from diffusing in polyimideresin, and improve the migration-resistant performance. To constitutethe high-melting point metal layer 20, it is possible to use any one ofnickel, chromium, molybdenum, platinum, titanium, and tungsten or analloy of these metals.

It is enough that the high-melting-point metal layer 20 functions as abarrier for preventing thermal diffusion of copper and the minimumthickness of the layer 20 is used for a thickness for performing abarrier function but the thickness is not restricted. However, when thelayer 20 has a thickness of 20 nm or more, a purposed effect may beobtained. Moreover, when the high-melting-point metal layer 20 becomestoo thick, the load by etching increases. Therefore, it is preferable touse a thickness of 30 nm or less because it is preferable to minimizethe thickness. In this case, components used to constitute thehigh-melting-point metal layer and the above binder metal layer aresimilar but thicknesses and purposed functions are different. That is,the binder metal layer may function as an intermediate layer forimproving the barrier characteristic and adhesiveness but thehigh-melting-point metal layer functions as only a barrier layer.

Copper foil provided with high-melting-point metal layer and bindermetal layer: Functions of a high-melting-point metal layer and a bindermetal layer are described above. Therefore, as shown in FIGS. 5(a),5(b-1), and 5(b-2), it is possible to use a copper foil simultaneouslyprovided with a high-melting-point metal layer and a binder metal layer.In this case, it is a principle to use a component for constituting thehigh-melting-point metal layer different from a component forconstituting the binder metal layer. Moreover, when the barrier functionof the binder metal layer is not sufficient, it can be said that thehigh-melting-point meta layer becomes necessary.

<Component for Constituting Dielectric Layer>

It is preferable to use any one of or two or more of aluminum oxide,tantalum oxide, and barium titanate for the inorganic-oxide sputter film3 for constituting a dielectric layer. The inorganic-oxide sputter film3 is not restricted when using a metal oxide usable as a dielectric.However, when using the sputtering vapor deposition method andconsidering the uniformity of film thickness and easiness in handling,it is preferable to form the film 3 by using any one of or two or moreof aluminum oxide, tantalum oxide, and barium titanate. Because theinorganic-oxide sputter film 3 constitutes the dielectric layer 6, thethickness of the inorganic sputter film 3 influences the thickness ofthe dielectric layer 6 and decides the final capacitor electriccapacity. Therefore, it is preferable that the thickness is as small aspossible. In fact, however, it is necessary to set the thickness to 1 μmor more. Otherwise, the number of pit-like defective portions 4 of theinorganic-oxide sputter film 3 is greatly increased and it cannot besaid that the uniformity of a film thickness is preferable. Moreover, itis allowed to optionally decide vacuum degree, target layout, type ofsputtering ion, and presence or absence of cleaning sputtering which areconditions used for the sputtering vapor deposition method used here byconsidering the characteristic of an apparatus and these conditions arenot matters to be restricted.

Moreover, the thickness of the inorganic-oxide sputter film 3 purposes a1.0 μm or less. In the case of an inorganic-oxide sputter film having athickness of 1.0 μm or less, the pit-like defective portion 4 easilyoccurs. That is, when the thickness exceeds 1.0 μm, the pit-likedefective portion 4 at a level requiring sealing by a polyimide resindoes not easily occur.

Furthermore, polyimide resin used for sealing of the pit-like defectiveportion 4 may be constituted by only a polyimide resin component orpolyimide resin obtained by dispersing dielectric fillers in thepolyimide resin component. By containing dielectric fillers, it ispossible to raise the dielectric constant of the dielectric layer 6 andincrease the electric capacity of a capacitor. The dielectric filler isdescribed in detail in the following manufacturing method.

<Variation of Dielectric-Layer-Provided Copper Foil>

Variation I: A dielectric-layer-provided copper foil is manufacturedwhen using a general copper foil and is a dielectric-layer-providedcopper foil in which a dielectric layer is used so as to directlycontact with the surface of a copper foil. Dielectric-layer-providedcopper foils 1A and 1A′ respectively constituted by two layers such as acopper foil layer and a dielectric layer shown in FIG. 1 are used.

Variation II: A dielectric-layer-provided copper foil constituted byforming a binder metal layer on the surface of a copper foil and forminga dielectric layer on the surface of the binder metal layer is used.Dielectric-layer-provided copper foils 1C and 1C′ shown in FIG. 3 areused which are respectively constituted by three layers consistingessentially of a copper foil layer, a binder metal layer, and adielectric layer.

Variation III: A dielectric-layer-provided copper foil is used in whicha high-melting-point metal layer is formed on the surface of a copperfoil and a dielectric layer is formed on the surface of thehigh-melting-point metal layer. Dielectric-layer-provided copper foils1D and 1D′ shown in FIG. 4 are used which are respectively constitutedby three layers consisting essentially of a copper foil layer, ahigh-melting-point metal layer, and a dielectric layer.

Variation IV: A dielectric-layer-provided copper foil is used in which ahigh-melting-point metal layer and a binder metal layer are formed onthe surface of a copper foil and a dielectric layer is formed on thesurface of the binder metal layer. Dielectric-layer-provided copperfoils 1E and 1E′ shown in FIG. 5 are used which are respectivelyconstituted by four layers consisting essentially of a copper foillayer, a high-melting-point metal layer, a binder metal layer, and adielectric layer.

Variation V: Dielectric-layer-provided copper foils 1B and 1B′ shown inFIG. 2 are used in which a dielectric layer is respectively formed onthe surface of a carrier-foil-provided copper foil by using thecarrier-foil-provided copper foil instead of the above copper foil.Though each dielectric-layer-provided copper foil is provided with acarrier foil, it is also possible to form the high-melting-point metallayer 20 or binder metal layer 12 between the copper foil layer 2 andthe dielectric layer 6 and adopt various variations shown in FIG. 6.

B. Dielectric-Layer-Provided Copper Foil Manufacturing Method

A dielectric-layer-provided copper foil manufacturing method of thepresent invention basically employs the following steps I. and II. Thatis, I. An inorganic-oxide sputter film having a thickness of 1.0 μm orless is formed on one side of a copper foil by using the sputteringvapor deposition method. II. Then, a pit-like defective portiongenerated on the inorganic-oxide sputter film is embedded and sealed byusing the electrodeposition method of polyimide resin.

Manufacturing method relating to copper foil: For the copper foil usedhere is not followed by restriction of a manufacturing method orpresence or absence of roughing like the above mentioned. However, whenusing the dielectric-layer-provided copper foils 1C and 1C′ respectivelyprovided with the binder metal layer 12 shown in FIG. 3, thedielectric-layer-provided copper foils 1D and 1D′ respectively providedwith the high-melting-point metal layer 20 shown in FIG. 4, or thedielectric-layer-provided copper foils 1E and 1E′ respectively providedwith the high-melting-point metal layer 20 and the binder metal layer 12shown in FIG. 5, it is necessary to form a high-melting-point metallayer or binder metal layer on the surface of a copper foil at thisstage. To form the high-melting-point metal layer or binder metal layer,it is possible to use any one of the wet electrolytic method andnon-electrolytic method, dry vapor deposition, sputtering, ion plating,and CVD in accordance with a component. A film having a uniformthickness is formed on the surface of a copper foil by optionallyselecting any one of the above thin film forming methods. In the case ofthe above thin film forming methods, it is not necessary to consider amanufacturing condition and description of each thin film forming methodis unnecessary.

Forming method of inorganic-oxide sputter film for constitutingdielectric layer: Then, for the sputtering vapor deposition method whenforming an inorganic-oxide sputter film on the surface of a copper foil,it is allowed to execute the method by adjusting conditions inaccordance with the rule. Therefore, description may be unnecessary.Therefore, the electrodeposition method of polyimide resin is describedbelow. In the case of the electrodeposition method of polyimide resin,it is possible to securely embed (seal) the pit-like defective portionof an inorganic-oxide sputter film in a complex and minute concave shapeand moreover, the electrodeposited film of polyimide resin becomes auniform film free from a defect such as a pinhole.

Polyimide resin used for sealing and the sealing method: In the case ofthe present invention, it is preferable to use the electrodepositedpolyimide method for sealing. Because the polyimide resin used for theelectrodeposited polyimide method is hardly dissolved in a solvent, apolyimide film is formed by electrodepositing the state of polyamideacid which is an anterior of the polyimide resin, heating it at a hightemperature, and thereby dehydrating and ring-forming it. However, thepolyimide acid has a disadvantage that it is easily decomposed andunstable. Therefore, in the case of the present invention, it ispreferable to form a polyimide film by using polyimide electrodepositedsolution for an anion electrodepositing composition using a multiblockpolyimide soluble in a solvent containing a pendant carboxyl group.Therefore, it is possible to obtain the polyimide electrodepositedsolution of this type in a market and there are some commercialpolyimide electrodeposited solutions having very superior performances.

To form a polyimide film on an inorganic-oxide sputter film by using thepolyimide electrodeposited solution, the electrodepositioncharacteristic depends on the type of the inorganic-oxide sputter film.Therefore, it is necessary to adjust a polyimide electrodepositedsolution depending on the type of an inorganic-oxide sputter filmserving as an object to be covered for forming a polyimide film.Generally, to form a polyimide film on an inorganic-oxide sputter filmin accordance with the electrodeposition method, when only embedding thepit-like defective portion of an inorganic-oxide sputter film as shownin FIG. 1(b-1), it is considered that a smaller particle diameter of acolloid particle is more superior in embedding performance of multiblockpolyimide in a polyimide electrodeposited solution and it is necessaryto decrease the colloid particle in diameter by increasing the quantityof a solvent. However, as shown in FIG. 1(b-2), when embedding thepit-like defective portion of an inorganic-oxide sputter film andforming a uniform film, it is necessary to simultaneously achieve theaction of embedding and the action of uniform film formation. Therefore,the particle diameter of colloid particle of multiblock polyimide in apolyimide electrodeposited solution must have a proper value. Moreover,an intimate relation with a particle diameter of a colloid particle ofmultiblock polyimide and a film thickness which can be realized ispresent. Therefore, when manufacturing the dielectric-layer-providedcopper foils 1A′, 1B′, 1C′, 1D′, and 1E′ shown in FIG. 1(b-2) byconsidering these things, it is necessary to adjust the diameter of acolloid particle in a polyimide electrodeposited solution to a properrange capable of keeping the balance with the polyimide film thickness,uniform electrodeposition characteristic, and embedding characteristic.

Then, the polyimide resin electrodeposition method can also use adielectric-filler-containing polyimide electrodeposited solutionobtained by containing dielectric fillers in a polyimideelectrodeposited solution. In the case of the dielectric-layer-providedcopper foils 1A, 1B, 1C, 1D, and 1E shown in FIG. 1(b-1), it is notalways necessary that a dielectric filler is present on a pit-likedefective portion. The method is particularly effective for thedielectric-layer-provided copper foils 1A′, 1B′, 1C′, 1D′, and 1E′ shownin FIG. 1(b-2), FIG. 2(b-2), and FIG. 3(b-2).

Dielectric filler contained in polyimide resin: Dielectric fillers usedin this case “have an average particle diameter D_(IA) of 0.05 to 1.0μm, an accumulated particle diameter D₅₀ by thelaser-diffraction-scattering particle-size-distribution measuring methodranges between 0.1 and 2.0 μm, and it is preferable to use dielectricpowder having a perovskite structure of a substantially spherical shapein which a cohesion degree shown by D₅₀/D_(IA) by using the accumulatedparticle diameter D₅₀ and the average particle diameter D_(IA) obtainedfrom an image analysis is 4.5 or less.”

Originally, in the case of the present invention, it can be said thatthe composition of the polyimide electrolytic solution should be decidedby considering up to the dispersing property of dielectric fillers to bedispersed in the polyimide electrolytic solution. However, the number oftypes of polyimide electrodeposited solutions containing multiblockpolyimide capable of forming a uniform polyimide film free from defectat the present technical level is limited and the adjustment range ofthe compositions is limited.

Therefore, the present inventors et al. secured a preferable dispersingproperty of dielectric fillers into a polyimide electrodepositedsolution by improving the powder aspect of dielectric fillers.Dielectric fillers used for the present invention are made present bydispersing them in a dielectric-filler-containing polyimide film,finally function as the dielectric layer of a capacitor, and are used toincrease the electric capacity of a capacitor when they are formed intoa capacitor shape. The dielectric filler uses dielectric powder ofcomposite oxide having a perovskite structure such as BaTiO₃, SrTiO₃,Pb(Zr—Ti)O₃ (common name of PZT), PbLaTiO₃.PbLaZro (common name ofPLZT), or SrBi₂T₂O₉ (common name of SBT).

Moreover, in the case of the powder characteristic of the dielectricfillers, the particle diameter must range between 0.05 and 1.0 μm. Theparticle diameter in this case, particles form a constant secondarycohesion state. Therefore, it is impossible to use thelaser-diffraction-scattering particle-size-distribution measuring methodor BET method because the accuracy is deteriorated by the indirectmeasurement of measuring an average particle diameter from the measuredvalue by the laser-diffraction-scattering particle-size-distributionmeasuring method or BET method. The particle diameter in thisdescription is an average particle diameter obtained by directlyobserving a dielectric filler by a scanning electron microscope (SEM)and image-analyzing the SEM image. In this description, the particlediameter in this case is shown as “D_(IA)”. In the case of the imageanalysis of dielectric filler powder observed by using the scanningelectron microscope (SEM) in this description, the average particlediameter D_(IA) is obtained by using the model IP-1000PC made by ASAHIENGINEERING CO., LTD. and assuming the circle-degree threshold value as10 and the overlap degree as 20.

Moreover, it is requested that the dielectric powder is used which has aperovskite structure having a substantially spherical shape in which theaccumulated particle diameter D₅₀ measured by thelaser-diffraction-scattering particle-size-distribution measuring methodranges between 0.1 and 2.0 μm and the cohesion degree shown byD₅₀/D_(IA) by using the accumulated particle diameter D₅₀ and averageparticle diameter D_(IA) obtained through image analysis is 4.5 or less.

The accumulated particle diameter D₅₀ measured by thelaser-diffraction-scattering particle-size-distribution measuring methoddenotes a particle diameter at an accumulation of 50% obtained by usingthe laser-diffraction-scattering particle-size-distribution measuringmethod and as the accumulated particle diameter D₅₀ decreases, the rateof particulate in the particle diameter distribution of dielectricfiller powder increases. In the case of the present invention, it isrequested that the value of the rate ranges between 0.1 and 2.0 μm. Thatis, when the value of the accumulated particle diameter D₅₀ is less than0.1 μm, progress of cohesion is extreme for dielectric filler powderobtained through any manufacturing method and the cohesion degreeddescribed below is not satisfied. However, when the value of theaccumulated particle diameter D₅₀ exceeds 1.0 μm, it is impossible touse the dielectric filler for forming a built-in capacitor layer of aprinted wiring board purposed by the present invention. That is, adielectric layer of a both-side copper clad laminate used to form abuilt-in capacitor layer normally has a thickness of 10 to 25 μm.Therefore, to uniformly disperse dielectric fillers, 2.0 μm-thicknessbecomes an upper limit.

The accumulated particle diameter D₅₀ in the present invention ismeasured by dispersing dielectric filler powder in methyl ethyl ketoneand putting the solution in the circulator of alaser-diffraction-scattering particle-size-distribution measuringapparatus, Micro Trac HRA 9320-X100 type (made by NIKKISO CO., LTD.).

In this case, the concept of cohesion degree is used, which is adoptedfrom the following reason. That is, it is considered that the value ofthe accumulated particle diameter D₅₀ obtained by using thelaser-diffraction-scattering particle-size-distribution measuring methodis not obtained by directly observing diameters of particulates one byone. Particulates constituting most dielectric powder are not theso-called single dispersion powder in which individual particles arecompletely separated but several particles cohere and group. Thelaser-diffraction-scattering particle-size-distribution measuring methodcaptures coherent particulates as one particle (coherent particle) andcalculates an accumulated particle diameter.

However, the average particle diameter D_(IA) obtained byimage-processing an observed image of dielectric powder observed byusing a scanning electron microscope is directly obtained from an SEMobservation image. Therefore, primary particles are securely capturedbut present of the coherent state of particulates is not reflected atall.

When considering the above mentioned, the present inventors et al.capture the value calculated with D₅₀/D_(IA) as a cohesion degree byusing the accumulated particle diameter D₅₀ obtained from thelaser-diffraction-scattering particle-size-distribution measuring methodand the average particle diameter D_(IA) obtained from image analysis.That is, when considering the above-describe theory by assuming thatvalues of D₅₀ and D_(IA) can be measured at the same accuracy in copperpowder of the same lot, it is considered that the value of D₅₀ forreflecting a coherent state on a measured value is larger than the valueof D_(IA) (the same result is obtained from real measurement).

In this case, the value of D₅₀ boundlessly approaches to the value ofD_(IA) when the coherent state of particulates of dielectric fillerscompletely disappears and the value of D₅₀/D_(IA) which is a cohesiondegree approaches to 1. When the cohesion degree becomes 1, singledispersion powder completely free from the coherent state ofparticulates is obtained. In fact, however, there is a case in which acohesion degree shows a value of less than 1. In the case of a completesphere theoretically thought, the cohesion degree does not become avalue less than 1. In fact, however, because a particulate is not acomplete sphere, a cohesion degree of less than 1 is requested.

In the case of the present invention, it is requested that the cohesiondegree of the dielectric filler powder is 4.5 or less. When the cohesiondegree exceeds 4.5, the coherent level between particulates of thedielectric filler becomes too high and uniform mixing with the abovepolyimide electrodeposited solution becomes difficult.

Even if adopting as a method for production of dielectric filler any oneof the alcoxide method, hydrothermal synthesis method, and oxalatemethod, a dielectric filler not satisfying the above cohesion degree isproduced because a constant coherent state is inevitably formed.Therefore, dielectric filler powder not satisfying the above cohesiondegree is produced. Particularly, in the case of the hydrothermalsynthesis method which is a wet method, formation of a coherent statetends to easily occur. Therefore, by performing the particle separationprocessing for separating the coherent powder into particulates one byone, it is possible to keep the coherent state of dielectric fillerpowder in the above cohesion degree range.

When simply purposing to perform particle separation work, it ispossible to use any one of the high-energy ball mill, high-speedconductor-collision air-flow-type crusher, collision crusher, gaugemill, medium agitation mill, and high-water-pressure crusher. However,to secure the mixing property and dispersing property of dielectricfiller powder and polyimide electrodeposited solution, it should beconsidered to reduce the viscosity of the dielectric-filler-containingpolyimide electrodeposited solution described below. To reduce theviscosity of the dielectric-filler-containing polyimide electrodepositedsolution, it is requested to decrease the specific surface area of adielectric filler particulate and smooth the particulate. Therefore,even if particle separation can be made, a particle separation methodshould not be used which damages the surface of a particulate at thetime of particle separation and increases the specific surface area.

As a result that the present inventors et al. studied with all theirhearts in accordance with the above recognition, it was found that twomethods were effective. A point common to these two methods is in thateach of the two methods is a method capable of sufficiently performingparticle separation by minimizing the contact of particulates ofdielectric filler powder with the inner wall, agitation blade, orcrushing medium of an apparatus and making coherent particulates collidewith each other. That is, contact with portions of the inner wall,agitation blade, or crushing medium of the apparatus results in damagingthe surface of a particulate, increasing the surface roughness, ordeteriorating the sphericity and this is prevented. Moreover, by causingsufficient mutual collision of particulates, coherent-state particulatesare separated from each other and at the same time, it is possible toadopt techniques capable of smoothing the particulate surface by themutual collision of particulates.

One of the techniques is to separate coherent-state dielectric fillerpowder by using a jet mill. The “jet mill” in this case performsparticle separation by using a high-speed air flow, thereby puttingdielectric filler powder into the air flow, making particulates collidewith each other in the high-speed air flow, and performing particleseparation.

Moreover, slurry of the coherent-state dielectric filler powderdispersed in the solvent which does not break the stoichiometry of theslurry is separated by using a fluid mill using centrifugal force. Inthis case, by using the “fluid mill using centrifugal force,” the slurryis flown at a high speed so as to draw a circular trajectory andparticulates cohering by the centrifugal force generated in this caseare made to collide with each other to perform particle separation.Thus, by cleaning, filtering, and drying the slurry completing particleseparation, the dielectric filler powder completing particle separationcan be obtained. By using the above-described method, it is possible toadjust the cohesion degree and smooth the surface of the dielectricfiller powder.

Moreover, to disperse particulates of dielectric fillers, it ispreferable to use a high-speed-rotation thin film method which is onetype of wet dispersing units. The high-speed-rotation thin film methodis briefly described below. An apparatus used for the above method is anagitator including an agitating blade having the diameter almost equalto the diameter of the inner wall of a cylindrical agitating bathinside. A cyclon flow is generated by injecting material slurry(“solvent in which dielectric fillers are dispersed” in the case of thepresent invention) into the bottom of the agitating bath and rotatingthe agitating blade at a high speed, the material slurry starts rotationand forms a rotation thin film along the inner wall of the agitatingbath. The rotation thin film is pressed against the inner wall of avessel by receiving a large force at an acceleration due to centrifugalforce and thereby, dielectric filler particulates roll in the inner wallsurface of the vessel, and dispersion processing can be made so as to beremoved from the surface of coherent particles. In this case, theparticulates do not collide with the inner wall surface but theparticulates contact with the inner wall surface while rolling.Therefore, particulate surface is not easily damaged or the specificsurface area of particulates is not increased, and the surface smoothingeffect of the particulates can be rather expected.

By using the high-speed rotation thin film method, the dispersion effectfor eliminating the coherent state of particles of dielectric fillersand the effect for sharpening the particle size distribution of thedielectric fillers can be obtained and the re-cohesion which isfrequently observed when adopting the normal agitation dispersion methoddoes not easily occur. Thus, it is possible to improve the dispersionproperty of dielectric fillers.

The polyimide electrodeposited solution is mixed with the dielectricfillers described above to prepare a dielectric-filler-containingpolyimide electrodeposited solution. In the case of the blending ratiobetween the polyimide electrodeposited solution and the dielectricfillers, it is preferable that the content of the dielectric fillers inthe dielectric-filler-containing polyimide electrodeposited solutionranges between 75 and 90 wt %.

When the content of the dielectric fillers is less than 75 wt %, it isimpossible to obtain the dielectric-constant improvement effect whenconstituting a capacitor. When the content of the dielectric fillersexceeds 90 wt %, the content of polyimide resin in a polyimide filmcontaining the dielectric fillers to be formed (hereafter referred to as“dielectric-filler-containing polyimide film”) becomes too low, thedielectric-filler-containing polyimide film becomes fragile, and thestrength of a dielectric layer is lowered.

Moreover, as the dielectric filler, it is preferable to use bariumtitanate among composite oxides respectively having a perovskitestructure when considering the manufacturing accuracy of powder at thisstage. In this case, it is possible to use temporary burned bariumtitanate or unburned barium titanate for the dielectric filler. Toobtain a high dielectric constant, it is preferable to use temporaryburned barium titanate. However, it is allowed to selectively use eitherof them in accordance with the design quality of a capacitor.

Furthermore, it is preferable that the dielectric filler of bariumtitanate has a cubic crystal structure. The crystal structure of bariumtitanate includes cubic crystal and tetragonal crystal. When using thedielectric filler of barium titanate having a cubic crystal structure,the value of the dielectric constant of a finally-obtained dielectriclayer is stabilized compared to the case of using a dielectric filler ofbarium titanate having only a tetragonal crystal structure. Therefore,it can be said that it is necessary to use barium titanate powder havingboth cubic crystal structure and tetragonal crystal structure.

By using the dielectric-filler-containing polyimide electrodepositedsolution described above and thereby forming adielectric-filler-containing polyimide film on the surface of ametal-oxide sputter film through the electrodeposition method,dielectric fillers are uniformly dispersed in thedielectric-filler-containing polyimide film and thedielectric-filler-containing polyimide film has a smooth surface and auniform film thickness and is free from defect.

C. Copper Clad Laminate for Forming Capacitor Layer

<Basic Configuration of Copper Clad Laminate for Forming CapacitorLayer>

A copper clad laminate of the present invention for forming a capacitorlayer is characterized in that it uses the copper foil layer of theabove-described dielectric-layer-provided copper foil of the presentinvention as a lower electrode forming layer and has an upper electrodeforming layer on the dielectric layer, uses a configuration of threelayers consisting essentially of a lower electrode forming layer, adielectric layer, and an upper electrode forming layer as a basicconfiguration. FIG. 7 shows schematic sectional views of copper cladlaminates 10A and 10A′ respectively having the above basicconfiguration. In this case, the term “copper clad laminate” is usedbecause a copper layer using a copper foil is present on at least oneface and it is not always necessary that the upper electrode forminglayer 11 is a layer formed by copper.

It is preferable that the upper electrode forming layer 11 uses any oneof components of copper, aluminum, silver, and gold. Though it isconsidered to use other metallic material, it is preferable in thecurrent status on the basis of the features of FIGS. 1(b-1) and 1(b-2)to use a metallic material superior in adhesiveness with a metal-oxidesputtering layer and polyimide layer for the upper electrode forminglayer 11 and copper, aluminum, silver, or gold is preferable as amaterial coinciding with these requests and superior in electricalcharacteristics.

In the case of the upper electrode forming layer 11, it is possible touse an electroless plating method or a method for combining copper foilstogether for copper. However, it is preferable to manufacture the layer11 in accordance with a dry system by using the sputtering vapordeposition method independently of a metallic material to be used fromthe viewpoint of keeping the thickness of a dielectric layer uniform.

Moreover, it is possible to form a high-melting-point metal layer and abinder metal layer between the upper electrode forming layer 11 and thedielectric layer 6 as described above for dielectric-layer-providedcopper foil. Therefore, a copper clad laminate of the present inventionfor forming a capacitor layer is provided with the variations describedbelow. The description and function relating to a high-melting-pointmetal layer and a binder metal layer are the same as the description ofthe above dielectric-layer-provided copper foil, the description isomitted in order to avoid duplicate description.

<Variation of Copper Clad Laminate for Forming Capacitor Layer>

Variation 1: By using a dielectric-layer-provided copper foil having adielectric layer so as to directly contact with the surface of a copperfoil used as a lower electrode, copper clad laminates 10A and 10A′ forrespectively forming a capacitor layer having a three layerconfiguration consisting essentially of a lower electrode forming layer,a dielectric layer, and an upper electrode forming layer are formed asshown in FIG. 7.

Variation 2: By using a dielectric-layer-provided copper foil having adielectric layer so as to directly contact with the surface of a copperfoil used as a lower electrode, copper clad laminates 10B and 10B′ forrespectively forming a capacitor layer having a four layer configurationconsisting essentially of a lower electrode forming layer, a dielectriclayer, a binder metal layer, and an upper electrode forming layer areformed as shown in FIG. 8.

Variation 3: By using a dielectric-layer-provided copper foil having adielectric layer so as to directly contact with the surface of a copperfoil used as a lower electrode, copper clad laminates 10C and 10C′ forrespectively forming a capacitor layer having a four layer configurationconsisting essentially of a lower electrode forming layer, a dielectriclayer, a high-melting-point metal layer, and an upper electrode forminglayer are formed as shown in FIG. 9.

Variation 4: By using a dielectric-layer-provided copper foil having adielectric layer so as to directly contact with the surface of a copperfoil used as a lower electrode, copper clad laminates 10D and 10D′ forrespectively forming a capacitor layer having a five layer configurationconsisting essentially of a lower electrode forming layer, a dielectriclayer, a binder metal layer, a high-melting-point metal layer, and anupper electrode forming layer are formed as shown in FIG. 10.

Variation 5: By using a dielectric-layer-provided copper foil having abinder metal layer between a copper foil used as a lower electrode and adielectric layer, copper clad laminates 10E and 10E′ for respectivelyforming a capacitor layer having a four layer configuration consistingessentially of a lower electrode forming layer, a binder metal layer, adielectric layer, and an upper electrode forming layer are formed asshown in FIG. 11.

Variation 6: By using a dielectric-layer-provided copper foil having abinder metal layer between a copper foil used as a lower electrode and adielectric layer, copper clad laminates 10F and 10F′ for respectivelyforming a capacitor layer having a five layer configuration consistingessentially of a lower electrode forming layer, a binder metal layer,dielectric layer, a binder metal layer, and an upper electrode forminglayer are formed as shown in FIG. 12.

Variation 7: By using a dielectric-layer-provided copper foil having abinder metal layer between a copper foil used as a lower electrode and adielectric layer, copper clad laminates 10G and 10G′ for respectivelyforming a capacitor layer having a five layer configuration consistingessentially of a lower electrode forming layer, binder metal layer,dielectric layer, high-melting-point metal layer, and an upper electrodeforming layer are formed as shown in FIG. 13.

Variation 8: BY sing a dielectric-layer-provided copper foil having abinder metal layer between a copper foil used as a lower electrode and adielectric layer, copper clad laminates 10H and 10H′ for respectivelyforming a capacitor layer having a six layer configuration consistingessentially of a lower electrode forming layer, a binder metal layer,dielectric layer, a binder metal layer, a high-melting-point metallayer, and an upper electrode forming layer are formed as shown in FIG.14.

Variation 9: By using a dielectric-layer-provided copper foil having ahigh-melting-point metal layer between a copper foil used as a lowerelectrode and a dielectric layer, copper clad laminates 10 i and 10 i′for respectively forming a capacitor layer having a four layerconfiguration consisting essentially of a lower electrode forming layer,a high-melting-point metal layer, a dielectric layer, and an upperelectrode forming layer are formed as sown in FIG. 15.

Variation 10: By using a dielectric-layer-provided copper foil having ahigh-melting-point metal layer between a copper foil used as a lowerelectrode and a dielectric layer, copper clad laminates 10J and 10J′ forrespectively forming a capacitor layer having a five layer configurationconsisting essentially of a lower electrode forming layer, ahigh-melting-point metal layer, a dielectric layer, a binder metallayer, and an upper electrode forming layer are formed as shown in FIG.16.

Variation 11: By using a dielectric-layer-provided copper foil having ahigh-melting-point metal layer between a copper foil used as a lowerelectrode and a dielectric layer, copper clad laminates 10K and 10K′ forrespectively forming a capacitor layer having a five layer configurationconsisting essentially of a lower electrode forming layer, ahigh-melting-point metal layer, a dielectric layer, a high-melting-pointmetal layer, and an upper electrode forming layer are formed as shown inFIG. 17.

Variation 12: By using a dielectric-layer-provided copper foil having ahigh-melting-point metal layer between a copper foil used as a lowerelectrode and a dielectric layer, copper clad laminates 10L and 10L′ forrespectively forming a capacitor layer having a six layer configurationconsisting essentially of a lower electrode forming layer, ahigh-melting-point metal layer, a dielectric layer, a binder metallayer, a high-melting-point metal layer, and an upper electrode forminglayer are formed as shown in FIG. 18.

Variation 13: By using a dielectric-layer-provided copper foil having ahigh-melting-point metal layer and a binder metal layer between a copperfoil used as a lower electrode and a dielectric layer, copper cladlaminates 10M and 10M′ for respectively forming a capacitor layer havinga five layer configuration consisting essentially of a lower electrodeforming layer, a high-melting-point metal layer, a binder metal layer, adielectric layer, and an upper electrode forming layer are formed asshown in FIG. 19. Variation 14: By using a dielectric-layer-providedcopper foil having a high-melting-point metal layer and a binder metallayer between a copper foil used as a lower electrode and a dielectriclayer, copper clad laminates 10N and 10N′ for respectively forming acapacitor layer having a six layer configuration consisting essentiallyof a lower electrode forming layer, a high-melting-point metal layer, abinder metal layer, a dielectric layer, a binder metal layer, and anupper electrode forming layer are formed as shown in FIG. 20.

Variation 15: By using a dielectric-layer-provided copper foil having ahigh-melting-point metal layer and a binder metal layer between a copperfoil used as a lower electrode and a dielectric layer, copper cladlaminates 10P and 10P′ for respectively forming a capacitor layer havinga six layer configuration consisting essentially of a lower electrodeforming layer, a high-melting-point metal layer, a binder metal layer, adielectric layer, a high-melting-point metal layer, and an upperelectrode forming layer are formed as shown in FIG. 21.

Variation 16: By using a dielectric-layer-provided copper foil having ahigh-melting-point metal layer and a binder metal layer between a copperfoil used as a lower electrode and a dielectric layer, copper cladlaminates 10Q and 10Q′ for respectively forming a capacitor layer havinga seven layer configuration consisting essentially of a lower electrodeforming layer, a high-melting-point metal layer, a binder metal layer, adielectric layer, a binder metal layer, a high-melting-point metallayer, and an upper electrode forming layer are formed as shown in FIG.22.

Which variation is adopted among the above-described variations isoptionally decided by considering the purpose and operating environmentof a final printed wiring board obtained by using a copper clad laminatefor forming a capacitor layer.

D. Advantages of the Present Invention

A dielectric-layer-provided copper foil of the present invention cancompletely prevent a short circuit between an upper electrode and alower electrode of a capacitor circuit obtained by using thedielectric-layer-provided copper foil because the copper foil isembedded by a pit-like defective-portion polyimide resin produced on ametal-oxide sputter film having a high dielectric constant even if usingthe sputter film for the configuration of a dielectric layer. Moreover,when a polyimide resin film covers a metal-oxide sputter film, it ispossible to prevent the metal-oxide sputter film constituting adielectric layer from damaging.

Therefore, a copper clad laminate for forming a capacitor layermanufactured by using the dielectric-layer-provided copper foil has athin dielectric layer having a uniform thickness and is able toeffectively prevent a short circuit between a lower electrode and anupper electrode. Therefore, the laminate has a high dielectric constant,makes it possible to improve an electrostatic capacity as a capacitor,and has a few defects. Therefore, the quality stability when forming acapacitor circuit is extremely improved. Moreover, when theabove-described high-melting-point metal layer is present, theadhesiveness between a dielectric layer and an electrode forming layeris improved because the high-melting-point metal layer is superior inmigration property and a binder metal layer is present.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention is described below through manufacturing of acopper clad laminate for forming a capacitor layer of a printed wiringboard.

EXAMPLE 1

In the case of this example, a dielectric-layer-provided copper foil 1A′shown in FIG. 1(b-2) was manufactured in accordance with themanufacturing flow shown below and a copper clad laminate 10A′ forforming a capacitor layer shown in FIG. 7(b) was manufactured by usingthe copper foil 1A′. This example used a very low profile (VLP) copperfoil having a nominal thickness of 18 μm but not undergoing a surfacetreatment as a copper foil 2 serving as a lower electrode forming layer.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

First, the surface of a copper foil having a size of 70 mm×70 mm wasacid-cleaned by 2N sulfuric acid solution (room temperature) to removecontaminant and extra oxide and dried. Then, the acid-cleaned copperfoil was put in the chamber of the sputtering vapor deposition system(CFS-12P-100). The sputtering condition was set so as to supply argongas to an ion gun at a flow rate of 87 cm³/min by setting the inside ofthe chamber to an ultimate vacuum of 1.2×10³ Pa. Then, the surface ofthe copper foil first completing acid cleaning was cleaned by inverselysputtering the surface with argon ions. The inverse sputteringconditions were set to an inverse sputtering power of 1,000 W and aninverse sputtering time of 10 min.

When the inverse sputtering of the surface of the copper foil wascompleted, oxygen gas was slowly leaked into the chamber of thesputtering vapor deposition system at a flow rate of 29 cm³/min. Then, atantalum target was used as a target, a sputtering power of 1,500 W, apresputtering time of 8 min, and sputtering time of 749.6 min were set,and a tantalum oxide film was formed on the surface of the copper foilas an inorganic-oxide sputter film having a thickness of approx. 1.0 μm.

As described above, the copper foil on whose one side the tantalum oxidefilm was formed was taken out from the chamber of the sputtering vapordeposition system and the pit-like defective portion of the tantalumoxide film was sealed by polyimide resin.

In the case of the electrodeposition method used for the sealing, thepolyimide electrodeposited solution GNW-100 made by PI GIJUTSU KENKYUSHOCo., Ltd. was used as a polyimide electrodeposited solution. Thepit-like defective portion of the tantalum oxide film was embedded byusing the polyimide electrodeposited solution and a polyimide resin filmwas formed on the surface. In this case, the dielectric-layer-providedcopper foil 1A′ shown in FIG. 1(b-2) was obtained by setting thetemperature of the polyimide electrodeposited solution to 25° C., usinga copper foil 2 on which a tantalum oxide film was formed as a positiveelectrode and a stainless steel plate as a negative electrode, applyinga DC voltage of 15 V to electrolyze it for 5 min and therebyelectrodeposited polyimide resin, embedding the pit-like defectiveportion of the tantalum oxide film, forming a polyimide resin filmhaving a thickness of 4 μm on the surface of the pit-like defectiveportion, cleaning the polyimide resin film by Q-AM-X068 made by PIGIJUTSU KENKYUSHO Co., Ltd. as a solvent for 30 min, holding the film inthe temperature atmosphere of 90° C. for 30 min, and then holding thefilm in the temperature atmosphere of 120° C. for 30 min, and raisingthe atmosphere temperature to 180° C. and holding it for 30 min, andfurther raising the atmosphere temperature to 250° C. and holding it for30 min, and thereby drying it.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

A copper layer having a thickness of 0.6 μm and serving as the upperelectrode forming layer 11 was formed on the surface of the dielectriclayer 6 by using the dielectric-layer-provided copper foil 1A′ obtainedas described above and the sputtering vapor deposition method for thesurface of the dielectric layer 6.

The sputtering vapor deposition system and basic sputtering conditionused in this case were the same as described above. However, cleaning bythe inverse sputtering was omitted. Moreover, a copper target was usedas the target to be set in the chamber of the sputtering vapordeposition system, presputtering (presputtering power of 1,000 W andpresputtering time of 10 min) was performed, film forming sputtering(sputtering power of 3,000 W and sputtering time of 9.1 min) wasperformed, and a copper layer serving as the upper electrode forminglayer 11 and having a thickness of approx. 0.5 μm was formed on thesurface of the dielectric layer 6.

Thus, the copper clad laminate 10A′ for forming a capacitor layer formedby such three layers as the lower electrode forming layer 2, adielectric layer 6, and an upper electrode forming layer 11 shown inFIG. 7(b) was obtained. Thus, as a result of checking whether a shortcircuit occurred between the copper foil 2 serving as a lower electrodeforming layer and the upper electrode forming layer 11 at 20 places inthe state of the copper clad laminate thus manufactured, it wasimpossible to find a place where a short circuit occurred.

EXAMPLE 2

In the case of this example, the dielectric-layer-provided copper foil1A′ shown in FIG. 1(b-2) was manufactured in accordance with themanufacturing flow shown below and the copper clad laminate 10B′ forforming a capacitor layer shown in FIG. 8(b) was manufactured by usingthe copper foil 1A′. This example used a very low profile (VLP) copperfoil having a nominal thickness of 18 μm but not undergoing the surfacetreatment as the copper foil 2 serving as a lower electrode forminglayer.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

Because manufacturing of the dielectric-layer-provided copper foil 1A′shown in FIG. 1(b-2) was the same as the case of the Example 1, itsdescription was omitted in order to avoid duplicate description.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

The binder metal layer 12 was formed by using thedielectric-layer-provided copper foil 1A′ obtained as described aboveand applying the sputtering vapor deposition method to the surface ofthe dielectric layer 6. The binder metal layer 12 was formed by usingthe sputtering vapor deposition method. In the case of the sputteringvapor deposition system and basic sputtering condition used in thiscase, cleaning by inverse sputtering like the case of forming the upperelectrode forming layer 11 of the Example 1 was not performed. Moreover,a chromium target was used as the target to be set in the chamber of thesputtering vapor deposition system, presputtering (presputtering powerof 2,000 W and presputtering time of 8 min) was performed andfilm-forming sputtering (sputtering power of 2,000 W and sputtering timeof 1.3 min) was performed to form a chromium layer having a thickness ofapprox. 30 nm on the surface of the dielectric layer 6.

Moreover, a copper layer having a thickness of 0.5 μm and serving as theupper electrode forming layer 11 was formed on a chromium layer formedas the binder metal layer 12 by using the sputtering method same as thecase of the Example 1.

Thus, the copper clad laminate 10B′ for forming a capacitor layer formedby such four layers as the lower electrode forming layer 2, dielectriclayer 6, binder metal layer 12, and upper electrode forming layer 11shown in FIG. 8(b) was obtained. As a result of checking whether a shortcircuit occurred between the copper foil 2 serving as a lower electrodeforming layer and the upper electrode forming layer 11 at 20 places inthe state of the copper clad laminate thus manufactured, it wasimpossible to fine a place where a short circuit occurred.

EXAMPLE 3

In the case of this example, the dielectric-layer-provided copper foil1A′ shown in FIG. 1(b-2) was manufactured in accordance with themanufacturing flow shown below and the copper clad laminate 10C′ forforming a capacitor layer shown in FIG. 9(b) was manufactured by usingthe copper foil 1A′. In the case of this example, a very low profile(VLP) copper foil having a nominal thickness of 18 μm but not undergoinga surface treatment was used as the copper foil 2 serving as a lowerelectrode forming layer.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

Because manufacturing of the dielectric-layer-provided copper foil 1A′shown in FIG. 1(b-2) was the same as the case of the Example 1, itsdescription was omitted here in order to avoid duplicate description.

<Manufacturing a Copper Clad Laminate for Forming Capacitor Layer>

The high-melting-point metal layer 20 was formed on the surface of thedielectric layer 6 by using the dielectric-layer-provided copper foil1A′ obtained as described above and the sputtering vapor depositionmethod. The high-melting-point metal layer 20 was formed by using thesputtering vapor deposition method. In the case of the sputtering vapordeposition system and basic sputtering condition used in this case,cleaning by inverse sputtering like the case of forming the upperelectrode forming layer 11 of the Example 1 was omitted, a nickel targetwas used for the target set in the chamber of a sputtering vapordeposition system, presputtering (presputtering power of 2,000 W andpresputtering time of 5 min) was performed, and film-forming sputtering(sputtering power of 2,000 W and sputtering time of 1.5 min) wasperformed to form a nickel layer having a thickness of approx. 30 nm onthe surface of the dielectric layer 6.

Moreover, a copper layer having a thickness of 0.5 μm and serving as theupper electrode forming layer 11 was formed on a nickel layer formed asthe high-melting-point metal layer 20 by using the sputtering methodsame as the case of the Example 1.

Thus, the copper clad laminate 10C′ for forming a capacitor layer formedby such four layers consisting essentially of the lower electrodeforming layer 2, dielectric layer 6, high-melting-point metal layer 20,and upper electrode forming layer 11 shown in FIG. 9(b) was obtained. Asa result of checking whether a short circuit occurred between the copperfoil 2 serving as a lower electrode forming layer and the upperelectrode forming layer 11 at 20 places under the state of the copperclad laminate thus manufactured, it was impossible to find a place wherea short circuit occurred.

EXAMPLE 4

In the case of this example, the dielectric-layer-provided copper foil1A′ shown in FIG. 1(b-2) was manufactured in accordance with themanufacturing flow shown below and the copper clad laminate 10D′ forforming a capacitor layer shown in FIG. 10(b) was manufactured by usingthe foil 1A′. This example used a very low profile (VLP) having anominal thickness of 18 μm but not undergoing a surface treatment as thecopper foil 2 serving as a lower electrode forming layer.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

Because manufacturing of the dielectric-layer-provided copper foil 1A′shown in FIG. 1(b-2) was the same as the case of the Example 1, itsdescription was omitted in order to avoid duplicate description.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

A chromium layer having a thickness of 30 nm was formed as the bindermetal layer 12 by using the dielectric-layer-provided copper foil 1A′,applying the sputtering vapor deposition method to the surface of thedielectric layer 6, and using the sputtering method same as the case ofthe Example 2.

Moreover, a nickel layer having a thickness of 50 nm was formed as thehigh-melting-point metal layer 20 on a chromium layer formed as thebinder metal layer 12 similarly to the case of the Example 3.

Furthermore, a copper layer having a thickness of 5 μm and serving asthe upper electrode forming layer 11 was formed on thehigh-melting-point metal layer 20 by using the sputtering method usedfor the Example 1.

Thus, the copper clad laminate 10D′ for forming a capacitor layer formedby such four layers consisting essentially of the lower electrodeforming layer 2, dielectric layer 6, binder metal layer 12,high-melting-point metal layer 20, and upper electrode forming layer 11shown in FIG. 10(b) was obtained. As a result of checking whether ashort circuit occurred between the copper foil 2 serving as a lowerelectrode forming layer and the upper electrode forming layer 11 at 20places under the state of the copper clad laminate thus manufactured, itwas impossible to find a place where a short circuit occurred.

EXAMPLE 5

In the case of this example, the dielectric-layer-provided copper foil1C′ shown in FIG. 3(b-2) was manufactured in accordance with themanufacturing flow shown below and the copper clad laminate 10E′ forforming a capacitor layer shown in FIG. 11(b) was manufactured by usingthe copper foil 1C′. This example used a very low profile (VLP) copperfoil having a nominal thickness of 18 μm but not undergoing a surfacetreatment as the copper foil 2 serving as a lower electrode forminglayer.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

First, the surface of a copper foil having a size of 70 mm×70 mm wasacid-cleaned by 2N sulfuric acid solution (room temperature) to removecontaminant and extra oxide and dried. Then, the acid-cleaned copperfoil was put in the chamber of the sputtering vapor deposition system(CFS-12P-100). Sputtering conditions were set so that the inside of thechamber becomes an ultimate vacuum of 1.2×10⁻³ Pa and argon gas wassupplied to an ion gun at a flow rate of 87 cm³/min. Then, the surfaceof the copper foil whose acid cleaning was first completed was cleanedby inversely sputtering the surface by argon gas. The inverse sputteringconditions were set to an inverse sputtering power of 1,000 W and aninverse sputtering time of 10 min.

When inverse sputtering of the surface of the copper foil was completed,a chromium target was used as the target to be set in the chamber of thesputtering vapor deposition system, presputtering (presputtering powerof 1,000 W and presputtering time of 1.3 min) was performed andfilm-forming puttering (sputtering power of 2,000 W and sputtering timeof 5 min) was performed to form a chromium layer having a thickness ofapprox. 30 nm on the surface of the copper foil 2 as the binder metallayer 12.

Then, oxygen gas was slowly leaked into the chamber of the sputteringvapor deposition system at a flow rate of 29 cm³/min and a tantalumtarget was used as the target, and sputtering power of 1,500 W,presputtering time of 8 min, and sputtering time of 749.6 min were setto form a tantalum oxide film on the surface of the binder metal layer12 as an inorganic-oxide sputter film having a thickness of approx. 1.0μm.

Thus, the copper foil on whose one side the binder metal layer 12 andtantalum oxide film were formed was taken out from the chamber of thesputtering vapor deposition system and the pit-like defective portion ofthe tantalum oxide film was sealed by polyimide resin similarly to thecase of the Example 1. Thus, the dielectric-layer-provided copper foil1C′ shown in FIG. 3(b-2) was obtained.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

A copper layer having a thickness of 0.5 μm and serving as the upperelectrode forming layer 11 was formed on the surface of the dielectriclayer 6 by using the dielectric-layer-provided copper foil 1A′ obtainedas described above and the sputtering vapor deposition method. Thesputtering vapor deposition system and basic sputtering condition usedhere were the same as the case of the Example 1.

Thus, the copper clad laminate 10E′ for forming a capacitor layer formedby such four layers consisting essentially of the lower electrodeforming layer 2, binder metal layer 12, dielectric layer 6, and upperelectrode forming layer 11 shown in FIG. 11(b) was obtained. As a resultof checking whether a short circuit occurred between the copper foil 2serving as a lower electrode forming layer and the upper electrodeforming layer 11 at 20 places under the state of the copper cladlaminate thus manufactured, it was impossible to find a place where ashort circuit occurred.

EXAMPLE 6

In the case of this example, the dielectric-layer-provided copper foil1C′ shown in FIG. 3(b-2) was manufactured in accordance with themanufacturing flow shown below and the copper clad laminate 10F′ forforming a capacitor layer shown in FIG. 12(b) was manufactured by usingthe copper foil 1C′. This example used a very low profile (VLP) copperfoil having a nominal thickness of 18 μm but not undergoing a surfacetreatment as the copper foil 2 serving as a lower electrode forminglayer.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

Because manufacturing of the dielectric-layer-provided copper foil 1C′shown in FIG. 3(b-2) was the same as the case of the Example 5, itsdescription was omitted in order to avoid duplicate description.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

The binder metal layer 12 was formed by using thedielectric-layer-provided copper foil 1C′ obtained as described aboveand applying the sputtering vapor deposition method to the surface ofthe dielectric layer 6. In the case of the binder metal layer 12, achromium layer having a thickness of approx. 30 nm was formed on thesurface of the dielectric layer 6 similarly to the case of the Example2.

Moreover, a copper layer having a thickness of 1.0 μm and serving as theupper electrode forming layer 11 was formed on a chromium layer formedas the binder metal layer 12 by using the sputtering method used for theExample 1.

Thus, the copper clad laminate 10F′ for forming a capacitor layer formedby five layers consisting essentially of the lower electrode forminglayer 2, binder metal layer 12, dielectric layer 6, binder metal layer12, and upper electrode forming layer 11 shown in FIG. 12(b) wasobtained. As a result of checking whether a short circuit occurredbetween the copper foil 2 serving as a lower electrode forming layer andthe upper electrode forming layer 11 at 20 places under the state of thecopper clad laminate thus manufactured, it was impossible to find aplace where a short circuit occurred.

EXAMPLE 7

In the case of this example, the dielectric-layer-provided copper foil1C′ shown in FIG. 3(b-2) was manufactured in accordance with themanufacturing flow shown below and the copper clad laminate 10G′ forforming a capacitor layer shown in FIG. 13(b) by using the foil 1C′.This example used a very low profile (VLP) copper foil having a nominalthickness of 18 μm but not undergoing a surface treatment as the copperfoil 2 serving as a lower electrode forming layer.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

Because manufacturing of the dielectric-layer-provided copper foil 1C′shown in FIG. 3(b-2) was the same as the case of the Example 5, itsdescription was omitted in order to avoid duplicate description.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

The high-melting-point metal layer 20 was formed by using thedielectric-layer-provided copper foil 1C′ obtained as described aboveand applying the sputtering vapor deposition method to the surface ofthe dielectric layer 6. The high-melting-point metal layer 20 was formedby using the sputtering vapor deposition method. In the case of thesputtering vapor deposition system and basic sputtering condition usedin this case, cleaning by inverse sputtering like the case of formingthe upper electrode forming layer 11 of the Example 1 was omitted, anickel target was used as the target to be set in the chamber of asputtering vapor deposition system, presputtering (presputtering powerof 2,000 W and presputtering time of 5 min) was performed andfilm-forming sputtering (sputtering power of 2,000 W and sputtering timeof 1.5 min) was performed to form a nickel layer having a thickness ofapprox. 30 nm on the surface of the dielectric layer 6.

Moreover, a copper layer having a thickness of 1.0 μm and serving as theupper electrode forming layer 11 was formed on a nickel layer formed asthe high-melting-point metal layer 20 by using the sputtering methodsame as the case of the Example 1.

Thus, the copper clad laminate 10G′ for forming a capacitor layer formedby five layers consisting essentially of the lower electrode forminglayer 2, binder metal layer 12, dielectric layer 6, high-melting-pointmetal layer 20, and upper electrode forming layer 11 shown in FIG. 13(b)was obtained. As a result of checking whether a short circuit occurredbetween the copper foil 2 serving as a lower electrode forming layer andthe upper electrode forming layer 11 at 20 places under the state of thecopper clad laminate thus manufactured, it was impossible to find aplace where a short circuit occurred.

EXAMPLE 8

In the case of this example, the dielectric-layer-provided copper foil1C′ shown in FIG. 3(b-2) was manufactured in accordance with themanufacturing flow shown below and the copper clad laminate 10H′ forforming a capacitor layer shown in FIG. 14(b) was manufactured by usingthe copper foil 1C′. This example used a very low profile (VLP) copperfoil having a nominal thickness of 18 μm but not undergoing a surfacetreatment as the copper foil 2 serving as a lower electrode forminglayer.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

Because manufacturing of the dielectric-layer-provided copper foil 1C′shown in FIG. 3(b-2) was the same as the case of the Example 5, itsdescription is omitted in order to avoid duplicate description.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

A chromium layer having a thickness of 30 nm was formed as the bindermetal layer 12 by using the dielectric-layer-provided copper foil 1C′,applying the sputtering vapor deposition method to the surface of thedielectric layer 6, and using the sputtering method same as the case ofthe Example 2.

Moreover, a nickel layer having a thickness of 30 nm was formed as thehigh-melting-point metal layer 20 on the chromium layer formed as thebinder metal layer 12 similarly to the case of the Example 3.

Furthermore, a copper layer having a thickness of 0.5 μm and serving asthe upper electrode forming layer 11 was formed on thehigh-melting-point metal layer 20 b using the sputtering method same asthe case of the Example 1.

Thus, the copper clad laminate 10H′ for forming a capacitor layer formedby six layers consisting essentially of the lower electrode forminglayer 2, binder metal layer 12, dielectric layer 6, binder metal layer12, high-melting-point metal layer 20, and upper electrode forming layer11 shown in FIG. 14(b) was obtained. As a result of checking whether ashort circuit occurred between the copper foil 2 serving as a lowerelectrode forming layer and the upper electrode forming layer 11 at 20places under the state of the copper clad laminate thus manufactured, itwas impossible to find a place where a short circuit occurred.

EXAMPLE 9

In the case of this example, the dielectric-layer-provided copper foil1D′ shown in FIG. 4(b-2) was manufactured in accordance with themanufacturing flow shown below and the copper clad laminate 10 i′ forforming a capacitor layer shown in FIG. 15(b) was manufactured by usingthe copper foil 1D′. This example used a very low profile (VLP) copperfoil having a nominal thickness of 18 μm but not undergoing a surfacetreatment as the copper foil 2 serving as a lower electrode forminglayer.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

First, the surface of a copper foil having a size of 70 mm×70 mm wasacid-leaned by 2N sulfuric acid solution (room temperature) to removecontaminant and extra oxide and dried. Then, the acid-cleaned copperfoil was put in the chamber of the sputtering vapor deposition system(CFS-12P-100). Sputtering conditions were set so that the ultimatevacuum in the chamber was 1.2×10⁻³ Pa and argon gas was supplied to anion gun at a flow rate of 87 cm³/min. Moreover, the surface of thecopper foil whose acid cleaning was first completed was cleaned byinversely sputtering the surface with argon ions. The inverse sputteringconditions were set so to inverse sputtering power of 1,000 W andinverse sputtering time of 10 min.

When inverse sputtering of the surface of the copper foil was completed,a nickel target was used as the target to be set in the chamber of thesputtering vapor deposition system, presputtering (presputtering powerof 2,000 W and presputtering time of 5 min) was performed andfilm-forming sputtering (sputtering power of 2,000 W and sputtering timeof 1.5 min) was performed to form a nickel layer on the surface of thedielectric layer 6 as the high-melting-point metal layer 20 having athickness of approx. 30 nm.

Moreover, oxygen gas was slowly leaked into the chamber of thesputtering vapor deposition system at a flow rate of 29 cm³/min, atantalum target was used as the target, sputtering power was set to1,500 W, presputtering time was set to 8 min, and sputtering time wasset to 749.6 min to form a tantalum oxide film on the surface of thehigh-melting-point metal layer 20 as an inorganic-oxide sputter filmhaving a thickness of approx. 1.0

As described above, a copper foil on whose one side thehigh-melting-point metal layer 20 and the tantalum oxide film wereformed was taken out from the chamber of the sputtering vapor depositionsystem and the pit-like defective portion of the tantalum oxide film wassealed by polyimide resin similarly to the case of the Example 1. Thus,the dielectric-layer-provided copper foil 1D′ shown in FIG. 3(b-2) wasobtained.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

A copper layer having a thickness of 0.5 μm and serving as the upperelectrode forming layer 11 was formed on the surface of the dielectriclayer 6 by using the dielectric-layer-provided copper foil 1D′ obtainedas described above. The sputtering vapor deposition system and basicsputtering condition used here were the same as the case of the Example1.

Thus, the copper clad laminate 10 i′ for forming a capacitor layerformed by such four layers as the lower electrode forming layer 2,high-melting-point metal layer 20, dielectric layer 6, and upperelectrode forming layer 11 shown in FIG. 15(b) was obtained. As a resultof checking whether a short circuit occurred between the copper foil 2serving as a lower electrode forming layer and the upper electrodeforming layer 11 at 20 places under the state of the copper cladlaminate thus manufactured, it was impossible to find a place where ashort circuit occurred.

EXAMPLE 10

In the case of this example, the dielectric-layer-provided copper foil1D′ shown in FIG. 4(b-2) was manufactured in accordance with themanufacturing flow shown below and the copper clad laminate 10J′ forforming a capacitor layer shown in FIG. 16(b) was manufactured by usingthe copper foil 1D′. This example used a very low profile (VLP) copperfoil having a nominal thickness of 18 μm but not undergoing a surfacetreatment as the copper foil 2 serving as a lower electrode forminglayer.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

Because manufacturing of the dielectric-layer-provided copper foil 1D′shown in FIG. 4(b-2) was the same as the case of the Example 9, itsdescription was omitted in order to avoid duplicate description.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

The binder metal layer 12 was formed by using thedielectric-layer-provided copper foil 1D′ obtained as described aboveand applying the sputtering vapor deposition method to the surface ofthe dielectric layer 6. In the case of the binder metal layer 12, achromium layer having a thickness of approx. 30 nm was formed on thesurface of the dielectric layer 6 similarly to the case of the Example2.

Moreover, a copper layer having a thickness of 0.5 μm and serving as theupper electrode forming layer 11 was formed on the chromium layer formedas the binder metal layer 12 by using the sputtering method same as thecase of the Example 1.

Thus, the copper clad laminate 10J′ for forming a capacitor layer formedby five layers consisting essentially of the lower electrode forminglayer 2, high-melting-point metal layer 20, dielectric layer 6, bindermetal layer 12, and upper electrode forming layer 11 shown in FIG. 16(b)was obtained. As a result of checking whether a short circuit occurredbetween the copper foil 2 serving as a lower electrode forming layer andthe upper electrode forming layer 11 at 20 places under the state of thecopper clad laminate thus manufactured, it was impossible to find aplace where a short circuit occurred.

EXAMPLE 11

In the case of this example, the dielectric-layer-provided copper foil1D′ shown in FIG. 4(b-2) was manufactured in accordance with themanufacturing flow shown below and the copper clad laminate 10K′ forforming a capacitor layer shown in FIG. 17(b) was manufactured by usingthe copper foil 1D′. This example used a very low profile (VLP) copperfoil having a nominal thickness of 18 μm but not undergoing a surfacetreatment as the copper foil 2 serving as a lower electrode forminglayer.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

Manufacturing of the dielectric-layer-provided copper foil 1D′ shown inFIG. 4(b-2) was the same as the case of the Example 9, its descriptionwas omitted in order to avoid duplicate description.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

The high-melting-point metal layer 20 was formed by using thedielectric-layer-provided copper foil 1D′ obtained as described aboveand applying the sputtering vapor deposition method to the surface ofthe dielectric layer 6. The high-melting-point metal layer 20 was formedby using the sputtering vapor deposition method. In the case of thesputtering vapor deposition system and basic sputtering condition usedin this case, cleaning by inverse sputtering like the case of formingthe upper electrode forming layer 11 of the Example 1 was omitted, anickel target was used as the target to be set in the chamber of thesputtering vapor deposition system, presputtering (presputtering powerof 2,000 W and presputtering time of 5 min) was performed andfilm-forming sputtering (sputtering power of 2,000 W and sputtering timeof 1.5 min) was performed to form a nickel layer having a thickness ofapprox. 30 nm on the surface of the dielectric layer 6.

Moreover, a copper layer having a thickness of 0.5 μm and serving as theupper electrode forming layer 11 was formed on the nickel layer formedas the high-melting-point metal layer 20 by using the sputtering methodsame as the case of the Example 1.

Thus, the copper clad laminate 10K′ for forming a capacitor layer formedby five layers consisting essentially of the lower electrode forminglayer 2, high-melting-point metal layer 20, dielectric layer 6,high-melting-point metal layer 20, and upper electrode forming layer 11shown in FIG. 13(b) was obtained. As a result of checking whether ashort circuit occurred between the copper foil 2 serving as a lowerelectrode forming layer and the upper electrode forming layer 11 at 20places under the state of the copper clad laminate thus manufactured, itwas impossible to find a place where a short circuit occurred.

EXAMPLE 12

In the case of this example, the dielectric-layer-provided copper foil1D′ shown in FIG. 4(b-2) was manufactured in accordance with themanufacturing flow shown below and the copper clad laminate 10L′ forforming a capacitor layer shown in FIG. 18(b) was manufactured by usingthe copper foil 1D′. This example used a very low profile (VLP) copperfoil having a nominal thickness of 18 μm but not undergoing a surfacetreatment as the copper foil 2 serving as a lower electrode forminglayer.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

Because manufacturing of the dielectric-layer-provided copper foil 1D′shown in FIG. 4(b-2) was the same as the case of the Example 9, itsdescription was omitted in order to avoid duplicate description.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

A chromium layer having a thickness of 30 nm was formed as the bindermetal layer 12 by using the dielectric-layer-provided copper foil 1D′,applying the sputtering vapor deposition method to the surface of thedielectric layer 6, and using the sputtering method same as the case ofthe Example 2.

Moreover, a nickel layer having a thickness of 30 nm was formed on achromium layer formed as the binder metal layer 12 similarly to the caseof the Example 3 as the high-melting-point metal layer 20.

Furthermore, a copper layer having a thickness of 0.5 μm and serving asthe upper electrode forming layer 11 was formed on thehigh-melting-point metal layer 20 by using the sputtering method same asthe case of the Example 1.

Furthermore, the copper clad laminate 10L′ for forming a capacitorlayer, formed by six layers consisting essentially of the lowerelectrode forming layer 2, high-melting-point metal layer 20, dielectriclayer 6, binder metal layer 12, high-melting-point metal layer 20, andupper electrode forming layer 11 shown in FIG. 18(b) was obtained. As aresult of checking whether a short circuit occurred between the copperfoil 2 serving as a lower electrode forming layer and the upperelectrode forming layer 11 at 20 places under the state of the copperclad laminate thus manufactured, it was impossible to find a place wherea short circuit occurred.

EXAMPLE 13

In the case of this example, the dielectric-layer-provided copper foil1E′ shown in FIG. 5(b-2) was manufactured in accordance with themanufacturing flow shown below and the copper clad laminate 10M′ shownin FIG. 19(b) was manufactured by using the copper foil 1E′. Thisexample used a very low profile (VLP) copper foil having a nominalthickness of 18 μm but not undergoing a surface treatment as the copperfoil 2 serving as a lower electrode forming layer.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

First, the surface of a copper foil having a size of 70 mm×70 mm wasacid-cleaned by 2N sulfuric acid solution (room temperature) to removecontaminant and extra oxide and dried. Then, the acid-cleaned copperfoil was put in the chamber of the sputtering vapor deposition system(CFS-12F-100). Sputtering conditions were set so that the ultimatevacuum in the chamber was 1.2×10⁻³ Pa and argon gas was supplied to anion gun at a flow rate of 87 cm³/min. Moreover, the surface of thecopper foil whose acid cleaning was first completed was cleaned byinversely sputtering the surface with argon ions. The inverse sputteringconditions were set to inverse sputtering power of 1,000 W and inversesputtering time of 10 min.

When inverse sputtering of the surface of the copper foil was completed,a nickel target was used as the target to be set in the chamber of thesputtering vapor deposition system, presputtering (presputtering powerof 2,000 W and presputtering time of 5 min) was performed andfilm-forming sputtering (sputtering power of 2,000 W and sputtering timeof 1.5 min) was performed to form a nickel layer on the surface of thedielectric layer 6 as the high-melting point metal layer 20 having athickness of 30 nm.

Moreover, a chromium layer having a thickness of 30 nm was formed as thebinder metal layer 12 on a nickel layer formed as the high-melting pointmetal layer 20 similarly to the case of the Example 5.

Furthermore, a tantalum oxide film having a thickness of approx. 1.0 μmserving as an inorganic-oxide sputter film was formed on the surface ofthe high-melting-point metal layer 20 by slowly leaking oxygen gas intothe chamber of the sputtering vapor deposition system at a flow rate of29 cm³/min, using a tantalum target as the target, setting sputteringpower to 1,500 W, presputtering time of 8 min, and sputtering time of749.6 min.

Thus, a copper foil on whose one side the high-melting-point metal layer20, binder metal layer 12, and tantalum oxide film were formed was takenout from the chamber of the sputtering vapor deposition system and thepit-like defective portion of the tantalum oxide film was sealed bypolyimide resin similarly to the case of the Example 1. Thus, thedielectric-layer-provided copper foil 1E′ shown in FIG. 5(b-2) wasobtained.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

A copper layer having a thickness of 0.5 μm and serving as the upperelectrode forming layer 11 was formed on the surface of the dielectriclayer 6 by using the dielectric-layer-provided copper foil 1E′ thusobtained and applying the sputtering vapor deposition method. Thesputtering vapor deposition system and basic sputtering condition usedhere were the same as the case of the Example 1.

Thus, the copper clad laminate 10M′ for forming a capacitor layer formedby four layers consisting essentially of the lower electrode forminglayer 2, high-melting-point metal layer 20, binder metal layer 12,dielectric layer 6, and upper electrode forming layer 11 shown in FIG.15(b) was obtained. As a result of checking whether a short circuitoccurred between the copper foil 2 serving as a lower electrode forminglayer and the upper electrode forming layer 11 at 20 places under thestate of the copper clad laminate thus manufactured, it was impossibleto find a place where a short circuit occurred.

EXAMPLE 14

In the case of this example, the dielectric-layer-provided copper foil1E′ shown in FIG. 5(b-2) was manufactured in accordance with themanufacturing flow shown below and the copper clad laminate 10N′ forforming a capacitor layer shown in FIG. 20(b) was manufactured by usingthe copper foil 1E′. This example used a very low profile (VLP) copperfoil having a nominal thickness of 18 μm but not undergoing a surfacetreatment as the copper foil 2 serving as a lower electrode forminglayer.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

Because manufacturing of the dielectric-layer-provided copper foil 1E′shown in FIG. 5(b-2) was the same as the case of the Example 13, itsdescription was omitted in order to avoid duplicate description.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

The binder metal layer 12 was formed by using thedielectric-layer-provided copper foil 1E′ thus obtained and applying thesputtering vapor deposition method to the surface of the dielectriclayer 6. In the case of the binder metal layer 12, a chromium layerhaving a thickness of approx. 30 nm was formed on the surface of thedielectric layer 6 similarly to the case of the Example 2.

Then, a copper layer having a thickness of 0.5 μm and serving as theupper electrode forming layer 11 was formed on the chromium layer formedas the binder metal layer 12 by using the sputtering method same as thecase of the Example 1.

Thus, the copper clad laminate 10N′ for forming a capacitor layer formedby six layers consisting essentially of the lower electrode forminglayer 2, high-melting-point metal layer 20, binder metal layer 12,dielectric layer 6, binder metal layer 12, and upper electrode forminglayer 11 shown in FIG. 20(b) was obtained. As a result of checkingwhether a short circuit occurred between the copper foil 2 serving as alower electrode forming layer and the upper electrode forming layer 11at 20 places under the state of the copper clad laminate thusmanufactured, it was impossible to find a place where a short circuitoccurred.

EXAMPLE 15

In the case of this example, the dielectric-layer-provided copper foil1E′ shown in FIG. 5(b-2) was manufactured in accordance with themanufacturing flow shown below and the copper clad laminate 10P′ forforming a capacitor layer shown in FIG. 21(b) was manufactured by usingthe copper foil 1E′. This example used a very low profile (VLP) copperfoil having a nominal thickness of 18 μm but not undergoing a surfacetreatment as the copper foil 2 serving as a lower electrode forminglayer.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

Because manufacturing of the dielectric-layer-provided copper foil 1E′shown in FIG. 5(b-2) was the same as the case of the Example 13, itsdescription was omitted in order to avoid duplicate description.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

The high-melting-point metal layer 20 was formed by using thedielectric-layer-provided copper foil 1E′ manufactured as describedabove and apply the sputtering vapor deposition method to the surface ofthe dielectric layer 6. The high-melting-point metal layer 20 was formedby using the sputtering vapor deposition method. In the case of thesputtering vapor deposition system and basic sputtering condition usedin this case, cleaning by inverse sputtering like the case of formingthe upper electrode forming layer 11 of the Example 1 was omitted, anickel target was used for the target to be set in the chamber of thesputtering vapor deposition system, presputtering (presputtering powerof 2,000 W and presputtering time of 5 min) was performed, andfilm-forming sputtering (sputtering power of 2,000 W and sputtering timeof 1.5 min) to form a nickel layer having a thickness of 30 nm on thesurface of the dielectric layer 6.

Moreover, a copper layer having a thickness of 1.0 μm and serving as theupper electrode forming layer 11 was formed on the nickel layer formedas the high-melting-point metal layer 20 by using the sputtering methodsame as the case of the Example 1.

Thus, the copper clad laminate 10P′ for forming a capacitor layer formedby six layers consisting essentially of the lower electrode forminglayer 2, high-melting-point metal layer 20, binder metal layer 12,dielectric layer 6, high-melting-point metal layer 20, and upperelectrode forming layer 11 shown in FIG. 21(b) was obtained. As a resultof checking whether a short circuit occurred between the copper foil 2serving as a lower electrode forming layer and the upper electrodeforming layer 11 at 20 places under the state of the copper cladlaminate thus manufactured, it was impossible to find a place where ashort circuit occurred.

EXAMPLE 16

In the case of this example, the dielectric-layer-provided copper foil1E′ shown in FIG. 5(b-2) was manufactured in accordance with themanufacturing flow shown below and the copper clad laminate 10Q′ forforming a capacitor layer shown in FIG. 22(b) was manufactured by usingthe copper foil 1E′. This example used a very low profile (VLP) copperfoil having a nominal thickness of 18 μm but not undergoing a surfacetreatment as the copper foil 2 serving as a lower electrode forminglayer.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

Because manufacturing of the dielectric-layer-provided copper foil 1E′shown in FIG. 5(b-2) was the same as the case o the Example 13, itsdescription was omitted in order to above duplicate description.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

A chromium layer having a thickness of 30 nm was formed as the bindermetal layer 12 by using the dielectric-layer-provided copper foil 1E′and applying the sputtering vapor deposition method to the surface ofthe dielectric layer 6, and using the sputtering method same as the caseof the Example 2.

Moreover, a nickel layer having a thickness of 30 nm was formed as thehigh-melting-point metal layer 20 on the chromium layer formed as thebinder metal layer 12 similarly to the case of the Example 15.

Furthermore, a copper layer having a thickness of 0.5 μm and serving asthe upper electrode forming layer 11 was formed on thehigh-melting-point metal layer 20 by using the sputtering method same asthe case of the Example 1.

Thus, the copper clad laminate 10Q′ for forming a capacitor layer formedby seven layers consisting essentially of the lower electrode forminglayer 2, high-melting-point metal layer 20, binder metal layer 12,dielectric layer 6, binder metal layer 12, high-melting point metallayer 20, and upper electrode forming layer 11 shown in FIG. 22(b) wasobtained. As a result of checking whether a short circuit occurredbetween the copper foil 2 serving as a lower electrode forming layer andthe upper electrode forming layer 11 at 20 places under the state of thecopper clad laminate thus manufactured, it was impossible to find aplace where a short circuit occurred.

EXAMPLES 17 TO 32

In the case of the examples, dielectric fillers were used by dispersingthem in the polyimide electrodeposited solution used for sealing bypolyimide resin used for the Examples 1 to 16. Therefore, the Examples17 to 32 change sealing of the Examples 1 to 16 to the following method.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

In this case, only sealing was described but description on overlappedportions was omitted. In the case of the electrodeposition method usedfor sealing of the Examples 17 to 32, dielectric fillers were used bydispersing them in the polyimide electrodeposited solution. Thepolyimide electrodeposited solution user here was the same as that usedfor the Example 1 and barium titanate powder serving as dielectricfillers having the powder characteristic shown below was mixed anddispersed in the polyimide electrodeposited solution. The mixing ratewas set so as to be 80 wt % of the polyimide solid content of the abovedielectric-filler-containing polyimide electrodeposited solution. Powdercharacteristic of dielectric filler Average particle diameter (D_(IA))0.25 μm Accumulated particle diameter (D₅₀)  0.5 μm Coherence degree(D₅₀/D_(IA)) 2.0

The pit-like defective portion of the tantalum oxide film was embeddedwith the dielectric-filler-containing polyimide electrodepositedsolution manufactured as described above and a polyimide resin film inwhich dielectric fillers were dispersed was formed on the surface of thetantalum oxide film. The electrodeposition conditions in this case wereset so that the temperature of the polyimide electrodeposited solutionwas 25° C., a copper foil on which a tantalum oxide film was formed as apositive electrode, a stainless steel plate was used as a negativeelectrode, a DC voltage of 15 V was applied, and electrolysis wasperformed for 5 min. Thereby, polyimide resin was electrodeposited, thepit-like defective portion of the tantalum oxide film was embedded, apolyimide resin film having a thickness of approx. 0.4 μm was formed onthe surface of the tantalum oxide film, and rinsed and dried. Thereby,the dielectric-layer-provided copper foils 1A′, 1B′, 1C′, 1D′, and 1E′described in the Examples 1 to 16 were obtained.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

By using the dielectric-layer-provided copper foils 1A′, 1B′, 1C′, 1D′,and 1E′ obtained as described above, the copper clad laminates (10A′,10B′, 10C′, 10D′, 10E′, 10F′, 10G′, 10H′, 10 i′, 10J′, 10K′, 10L′, 10M′,10N′, 10P′, and 10Q′) were realized similarly to the case of steps ofthe Examples 1 to 16.

As a result of checking whether a short circuit occurred between thecopper foil 2 serving as a lower electrode forming layer and the upperelectrode forming layer 11 at 20 places under the state of the copperclad laminates thus manufactured, it was impossible to find a placewhere a short circuit occurred.

EXAMPLES 33 TO 48

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

Each of the example shown here used the carrier-foil-provided copperfoil shown in FIG. 2(a) instead of the copper foil 2 used for theExamples 1 to 16. In the case of the carrier-foil-provided copper foil,a junction interface layer was formed on the glossy face of anelectrolytic copper foil having a thickness of 35 μm as a carrier foiland a copper foil layer having a thickness of 5 μm was formed on thejunction interface layer. The junction interface layer was formed bycarboxybenzotriazole. Therefore, it was unnecessary to describe steps.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

By using the dielectric-layer-provides copper foils 1B, 1B(2), 1B(3),and 1B(4) shown in FIG. 6 obtained as described above, a layerconfiguration same as the layer configuration of each of the copper cladlaminates (10A′, 10B′, 1° C.′, 10D′, 10E′, 10F′, 10G′, 10H′, 10 i′,10J′, 10K′, 10L′, 10M′, 10N′, 10P′, and 1Q′) shown in FIG. 6 wasrealized similarly to each of steps of the Examples 1 to 16.

As a result of checking whether a short circuit occurred between thecopper foil 2 serving as a lower electrode forming layer and the upperelectrode forming layer 11 at 20 places under the state of the copperclad laminates thus manufactured, it was impossible to find a placewhere a short circuit occurred.

EXAMPLE 49

This example was only different from the Example 1 in that chromium wasused for the upper electrode forming layer of the Example 1. Therefore,description of portions duplicate with those of the Example 1 wasomitted.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

This step was completely the same as the case of the Example 1.Therefore, description here was omitted.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

A chromium layer having a thickness of 30 nm was formed as the upperelectrode forming layer 11 by using the dielectric-layer-provided copperfoil 1A′ obtained as described above shown in FIG. 1(b-2) and applyingthe sputtering vapor deposition method to the surface of the dielectriclayer 6.

Though the sputtering vapor deposition system and basic sputteringcondition used in this case were the same as the above described,cleaning by inverse sputtering was omitted. Moreover, a chromium targetwas sued for the target to be set in the chamber of the sputtering vapordeposition system, presputtering (presputtering power of 1,000 W andpresputtering time of 5 min) was performed, and film-forming sputtering(sputtering power of 2,000 W and sputtering time of 1.3 min) wasperformed to form a chromium layer having a thickness of approx. 30 nmserving as the upper electrode forming layer 11 on the surface of thedielectric layer 6.

Thus, the copper clad laminate 10A′ for forming a capacitor layer formedby such three layers as the lower electrode forming layer 2, dielectriclayer 6, and upper electrode forming layer 11 shown in FIG. 7(b) wasobtained. Moreover, as a result of checking whether a short circuitoccurred between the copper foil 2 serving as a lower electrode forminglayer and the upper electrode forming layer 11 at 20 places under thestate of a copper clad laminate similarly to the case of the Example 1,it was impossible to find a place where a short circuit occurred.

EXAMPLE 50

In the case of this example, a nickel-cobalt-alloy film was applied asthe high-melting-point metal layer 20 of each of the Examples 9 to 16.Moreover, as for the other features, the dielectric-layer-providedcopper foils 1D′ and 1E′and the copper clad laminates 10 i, 10J′, 10K′,10L′, 10M′, 10N′, 10P′, and 10Q′ for respectively forming a capacitorlayer were manufactured in accordance with the procedure of each of theExamples 9 to 16. Therefore, only formation of the high-melting-pointmetal layer 20 was described.

<Manufacturing of High-Melting-Point Metal Layer>

First, the surface of a copper foil having a size of 70 mm×70 mm wasacid-cleaned with 2N sulfuric acid solution (room temperature) to removecontaminant and extra oxide and dried. Then, a nickel-cobalt-alloy filmwas formed on the surface of the acid-cleaned copper foil as ahigh-melting-point metal layer using the electrolytic method. In thiscase, the nickel-cobalt-alloy film was electrolyzed in accordance withconditions of 130 g/l of cobalt sulfate, 100 g/l of nickel sulfate, 30g/l of boric acid, 12.5 g/l of potassium chloride, 8 g/l of sodiumdihydrogenphosphate, solution temperature of 40° C., pH of 4.0, andcurrent density of 7A/dm² to uniformly electrocyrstallize anickel-cobalt-alloy film having a thickness of 0.5 μm.

As a result of checking whether a short circuit occurred between thecopper foil 2 serving as a lower electrode forming layer and the upperelectrode forming layer 11 at 20 places under the state of the copperclad laminate thus manufactured, it was impossible to find a place wherea short circuit occurred.

COMPARATIVE EXAMPLE

In the case of this comparative example, a copper clad laminate forforming a capacitor layer was manufactured in accordance with amanufacturing flow almost same as the case of the Example 1. Thiscomparative example was different from the Example 1 in that adielectric layer does not undergo the sealing by polyimide resin.Therefore, the dielectric layer was constituted by only a tantalum oxidefilm.

<Manufacturing of Dielectric-Layer-Provided Copper Foil>

Acid-cleaning of the copper foil 2 and formation of a tantalum oxidefilm by the sputtering vapor deposition method were the same as the caseof the Example 1. Moreover, a copper foil on which the tantalum oxidefilm was formed was taken out from the chamber of the sputtering vapordeposition system. The copper foil was used as adielectric-layer-provided copper foil under this state.

<Manufacturing of Copper Clad Laminate for Forming Capacitor Layer>

A copper layer having a thickness of 0.5 μm serving as an upperelectrode forming layer was formed by using thedielectric-layer-provided copper foil thus manufactured and applying thesputtering vapor deposition method to the surface of the dielectriclayer of the copper foil similarly to the case of the Example 1. As aresult of checking whether a short circuit occurred between a copperfoil serving as a lower electrode forming layer and an upper electrodeforming layer at 20 places under the state of the copper clad laminatethus manufactured, it was possible to find eight places where a shortcircuit occurred.

INDUSTRIAL APPLICABILITY

A dielectric-layer-provided copper foil of the present invention issuitable for manufacturing of a built-in capacitor substrate of aprinted wiring board. Moreover, because a copper clad laminate forforming a capacitor layer manufactured by using thedielectric-layer-provided copper foil has a uniform thickness though adielectric layer is thin and is able to effectively prevent a shortcircuit from occurring between a lower electrode and an upper electrodeafter a capacitor circuit is formed, it is possible to extremely improvethe production yield of copper clad laminates respectively having acapacitor circuit.

1. A dielectric-layer-provided copper foil for forming a capacitorlayer, on whose one side, a dielectric layer is formed, characterized inthat: said dielectric layer is an inorganic-oxide sputter film formed onone side of a copper foil in accordance with a sputtering vapordeposition method and having a thickness of 1.0 μm or less and apit-like defective portion formed on the inorganic-oxide sputter film issealed by polyimide resin.
 2. The dielectric-layer-provided copper foilfor forming a capacitor layer according to claim 1, characterized inthat: an inorganic-oxide sputter film is formed by using any one of ortwo or more of aluminum oxide, tantalum oxide, and barium titanate. 3.The dielectric-layer-provided copper foil for forming a capacitor layeraccording to claim 1, characterized in that: polyimide resin containsdielectric filler.
 4. The dielectric-layer-provided copper foil forforming a capacitor layer according to claim 1, characterized in that: abinder metal layer is formed between a copper foil layer and adielectric layer.
 5. The dielectric-layer-provided copper foil forforming a capacitor layer according to claim 4, characterized in that: abinder metal layer is formed by any one selected from cobalt, chromium,nickel, nickel-chromium alloy, zirconium, palladium, molybdenum,tungsten, titanium, aluminum, platinum, and alloy of these metals. 6.The dielectric-layer-provided copper foil for forming a capacitor layeraccording to claims 1, characterized in that: a high-melting-point metallayer is formed between a copper foil layer and a dielectric layer. 7.The dielectric-layer-provided copper foil for forming a capacitor layeraccording to claim 6, characterized in that: a high-melting-point metallayer is formed by any one selected from nickel, chromium, molybdenum,platinum, titanium, tungsten, and alloy of these metals.
 8. Thedielectric-layer-provided copper foil for forming a capacitor layeraccording to claim 1, characterized in that: a high-melting-point metallayer and a binder metal layer are formed between a copper foil layerand a dielectric layer.
 9. A copper clad laminate for forming acapacitor layer, using the copper foil layer of thedielectric-layer-provided copper foil of claim 1 as a lower electrodeforming layer, characterized in that: an upper electrode forming layeris formed on the dielectric layer and a three-layer configuration formedby three layers consisting essentially of a lower electrode forminglayer, a dielectric layer, and an upper electrode forming layer is used.10. The copper clad laminate for forming a capacitor layer, using thecopper foil layer of the dielectric-layer-provided copper foil of claim1 as a lower electrode forming layer, characterized in that: a bindermetal layer and an upper electrode forming layer are formed on thedielectric layer and a four-layer configuration formed by four layers asa lower electrode forming layer, a dielectric layer, a binder metallayer, and an upper electrode forming layer is used.
 11. A copper cladlaminate for forming a capacitor layer, using the copper foil layer ofthe dielectric-layer-provided copper foil of claim 1 as a lowerelectrode forming layer, characterized in that: a high-melting-pointmetal layer and an upper electrode forming layer are formed on thedielectric layer and a four-layer configuration is used which is formedby four layers consisting essentially of a lower electrode forminglayer, a dielectric layer, a high-melting-point metal layer, and anupper electrode forming layer.
 12. A copper clad laminate for forming acapacitor layer, using the copper foil layer of thedielectric-layer-provided copper foil of claim 1 as a lower electrodeforming layer, characterized in that: a high-melting-point metal layer,a binder metal layer, and an upper electrode forming layer are formed onthe dielectric layer and a five-layer configuration is used which isformed by five layers consisting essentially of a lower electrodeforming layer, a dielectric layer, a binder metal layer, ahigh-melting-point metal layer, and an upper electrode forming layer.13. A copper clad laminate for forming a capacitor layer, using thecopper foil layer of the dielectric-layer-provided copper foil of claim4 as a lower electrode forming layer, characterized in that: an upperelectrode forming layer is formed on the dielectric layer and afour-layer configuration is used which is formed by four layersconsisting essentially of a lower electrode forming layer, a bindermetal layer, a dielectric layer, and an upper electrode forming layer.14. A copper clad laminate for forming a capacitor layer, using thecopper foil layer of the dielectric-layer-provided copper foil of claim4 as a lower electrode forming layer, characterized in that: a bindermetal layer and an upper electrode forming layer are formed on thedielectric layer and a five-layer configuration is used which is formedby five layers consisting essentially of a lower electrode forminglayer, a binder metal layer, a dielectric layer, a binder metal layer,and an upper electrode forming layer.
 15. A copper clad laminate forforming a capacitor layer, using the copper foil layer of thedielectric-layer-provided copper foil of claim 4 as a lower electrodeforming layer, characterized in that: a high-melting-point metal layerand an upper electrode forming layer are formed on the dielectric layerand a five-layer configuration is used which is formed by five layersconsisting essentially of a lower electrode forming layer, a bindermetal layer, a dielectric layer, a high-melting-point metal layer, andan upper electrode forming layer.
 16. A copper clad laminate for forminga capacitor layer, using the copper foil layer of thedielectric-layer-provided copper foil of claim 4 as a lower electrodeforming layer, characterized in that: a high-melting-point metal layer,a binder metal layer, and an upper electrode forming layer are formed onthe dielectric layer and a six-layer configuration is used which isformed by six layers consisting essentially of a lower electrode forminglayer, a binder metal layer, a dielectric layer, a binder metal layer, ahigh-melting-point metal layer, and an upper electrode forming layer.17. A copper clad laminate for forming a capacitor layer, using thecopper foil layer of the dielectric-layer-provided copper foil of claim6 as a lower electrode forming layer, characterized in that: an upperelectrode forming layer is formed on the dielectric layer and afour-layer configuration is used which is formed by four layersconsisting essentially of a lower electrode forming layer, ahigh-melting-point metal layer, a dielectric layer, and an upperelectrode forming layer.
 18. A copper clad laminate for forming acapacitor layer, using the copper foil layer of thedielectric-layer-provided copper foil of claim 6 as a lower electrodeforming layer, characterized in that: a binder metal layer and an upperelectrode forming layer are formed on the dielectric layer and afive-layer configuration is used which is formed by five layersconsisting essentially of a lower electrode forming layer, ahigh-melting-point metal layer, a dielectric layer, a binder metallayer, and an upper electrode forming layer.
 19. A copper clad laminatefor forming a capacitor layer, using the copper foil layer of thedielectric-layer-provided copper foil of claim 6 as a lower electrodeforming layer, characterized in that a high-melting-point metal layerand an upper electrode forming layer are formed on the dielectric layerand a five-layer configuration is used which is formed by five layersconsisting essentially of a lower electrode forming layer, ahigh-melting-point metal layer, a dielectric layer, a high-melting-pointmetal layer, and an upper electrode forming layer.
 20. A copper cladlaminate for forming a capacitor layer, using the copper foil layer ofthe dielectric-layer-provided copper foil of claim 6 as a lowerelectrode forming layer, characterized in that: a high-melting-pointmetal layer, a binder metal layer, and an upper electrode forming layerare formed on the dielectric layer and a six-layer configuration is usedwhich is formed by six layers consisting essentially of a lowerelectrode forming layer, a high-melting-point metal layer, a dielectriclayer, a binder metal layer, a high-melting-point metal layer, and anupper electrode forming layer.
 21. A copper clad laminate for forming acapacitor layer, using the copper foil layer of thedielectric-layer-provided copper foil of claim 8 as a lower electrodeforming layer, characterized in that: an upper electrode forming layeris formed on the dielectric layer and a five-layer configuration is usedwhich is formed by five layers consisting essentially of a lowerelectrode forming layer, a high-melting-point metal layer, a bindermetal layer, a dielectric layer, and an upper electrode forming layer.22. A copper clad laminate for forming a capacitor layer, using thecopper foil layer of the dielectric-layer-provided copper foil of claim8 as a lower electrode forming layer, characterized in that: a bindermetal layer and an upper electrode forming layer are formed on thedielectric layer and a six-layer configuration is used which is formedby six layers consisting essentially of a lower electrode forming layer,a high-melting-point metal layer, a binder metal layer, a dielectriclayer, a binder metal layer, and an upper electrode forming layer.
 23. Acopper clad laminate for forming a capacitor layer, using the copperfoil layer of the dielectric-layer-provided copper foil of claim 8 as alower electrode forming layer, characterized in that: ahigh-melting-point metal layer and an upper electrode forming layer areformed on the dielectric layer and a six-layer configuration is usedwhich is formed by six layers consisting essentially of a lowerelectrode forming layer, a high-melting-point metal layer, a bindermetal layer, a dielectric layer, a high-melting-point metal layer, andan upper electrode forming layer.
 24. A copper clad laminate for forminga capacitor layer, using the copper foil layer of thedielectric-layer-provided copper foil of claim 8 as a lower electrodeforming layer, characterized in that: a high-melting-point metal layer,a binder metal layer, and an upper electrode forming layer are formed onthe dielectric layer and a seven-layer configuration is used which isformed by seven layers consisting essentially of a lower electrodeforming layer, a high-melting-point metal layer, a binder metal layer, adielectric layer, a binder metal layer, a high-melting-point metallayer, and an upper electrode forming layer.
 25. A copper clad laminatefor forming a capacitor layer using the dielectric-layer-provided copperfoil of claim 9, characterized in that: an upper electrode forming layeruses any one of copper, aluminum, silver, and gold.
 26. A method formanufacturing the dielectric-layer-provided copper foil for forming acapacitor layer of claim 1, characterized in that: an inorganic-oxidesputter film having a thickness of 1.0 μm or less is formed on one sideof the copper foil by using the sputtering vapor deposition method, anda pit-like defective portion generated on the inorganic-oxide sputterfilm is embedded and sealed with polyimide resin by the polyimide-resinelectrodeposition method.
 27. A method for manufacturing adielectric-layer-provided copper foil for forming a capacitor layer ofclaim 4, characterized in that: a binder metal layer is formed on theone side of a copper foil, an inorganic-oxide sputter film having athickness of 1.0 μm or less is formed on the binder metal layer by usingthe sputtering vapor deposition method, and a pit-like defective portiongenerated on the inorganic-oxide sputter film is embedded and sealedwith polyimide resin by using the polyimide-resin electrodepositionmethod.
 28. The method for manufacturing a dielectric-layer-providedcopper foil for forming a capacitor layer according to claim 6,characterized in that: a high-melting-point metal layer is formed on theone side of a copper foil and an inorganic-oxide sputter film having athickness of 1.0 μm or less is formed on the high-melting-point metallayer by using the sputtering vapor deposition method, and a pit-likedefective portion generated on the inorganic-oxide sputter film isembedded and sealed with polyimide resin by using the polyimide-resinelectrodeposition method.
 29. The method for manufacturing thedielectric-layer-provided copper foil for forming a capacitor layeraccording to claim 8, characterized in that: a high-melting-point metallayer is formed on the one side of a copper foil and a binder metallayer is formed on the high-melting-point metal layer, and aninorganic-oxide sputter film having a thickness of 1.0 μm or less isformed on the binder metal layer by using the sputtering vapordeposition method, and a pit-like defective portion generated on theinorganic-oxide sputter film is embedded and sealed with polyimide resinby using the polyimide electrodeposition method.
 30. A method formanufacturing a dielectric-layer-provided copper foil for forming acapacitor layer according to claim 27, characterized in that: thepolyimide-resin electrodeposition method uses a dielectric-fillercontaining polyimide electrodeposited solution containing dielectricfillers in a polyimide electrodeposited solution, and dielectric powderhaving a substantially-spherical perovskite structure in which anaverage particle diameter D_(IA) ranges between 0.05 and 1.0 μm, anaccumulated particle diameter D₅₀ according to thelaser-diffraction-scattering particle-size-distribution measuring methodranges between 0.1 and 2.0 μm, and the value of coherence degree shownas D₅₀/D_(IA) by using the accumulated particle diameter D₅₀ and theaverage particle diameter D_(IA) obtained from an image analysis is 4.5or less is used for the dielectric fillers.
 31. The method formanufacturing a dielectric-layer-provided copper foil for forming acapacitor layer according to claim 30, characterized in that: thecontent of dielectric fillers in a dielectric-filler-containingpolyimide electrodeposited solution ranges between 75 and 90 wt %.